The new gg format is based on a BNF file which can be found in the `gg` directory. The code for decoding `.gg` files has been refactored to mirror that file. The result is more resilient parsing, better errors, and a greater ability to extend the format in the future. The new decoder is notable in that it does not use a lexer. Both lexing and parsing are done in a single step. The format syntax itself has also been modified. Rather than using semi-colons everywhere, commas are used as separators in tuples. Additionally the final comma/semi-colon is no longer required.master
parent
21c91731e9
commit
360857d506
@ -1,19 +1,24 @@ |
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out = { |
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* A function which accepts a number N and returns the Nth fibonacci number |
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{ |
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* We are passing a tuple of inputs into a graph here, such that the graph is |
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* evaluated as an anonymous function. That anonymous function uses recur |
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* internally to compute the result. |
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out = { |
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|
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decr = { out = add < (in; -1;); }; |
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* A little helper function. |
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decr = { out = add < (in, -1) }; |
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|
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n = tupEl < (in; 0;); |
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a = tupEl < (in; 1;); |
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b = tupEl < (in; 2;); |
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* Deconstruct the input tuple into its individual elements, for clarity. |
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* There will be a more ergonomic way of doing this one day. |
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n = tupEl < (in, 0); |
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a = tupEl < (in, 1); |
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b = tupEl < (in, 2); |
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|
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out = if < ( |
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isZero < n; |
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a; |
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recur < ( |
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decr < n; |
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b; |
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add < (a;b;); |
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out = if < ( |
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isZero < n, |
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a, |
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recur < ( decr<n, b, add<(a,b) ), |
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); |
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); |
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|
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} < (in; 0; 1;); |
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} < (in, 0, 1); |
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} |
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@ -1,353 +1,73 @@ |
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package gg |
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import ( |
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"errors" |
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"bufio" |
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"fmt" |
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"io" |
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"strconv" |
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|
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"github.com/mediocregopher/ginger/graph" |
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) |
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|
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// Type aliases for convenience
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type ( |
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Graph = graph.Graph[Value, Value] |
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OpenEdge = graph.OpenEdge[Value, Value] |
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) |
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|
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// Punctuations which are used in the gg file format.
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const ( |
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punctTerm = ";" |
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punctOp = "<" |
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punctAssign = "=" |
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punctOpenGraph = "{" |
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punctCloseGraph = "}" |
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punctOpenTuple = "(" |
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punctCloseTuple = ")" |
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) |
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|
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func decoderErr(tok LexerToken, err error) error { |
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return fmt.Errorf("%s: %w", tok.errPrefix(), err) |
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} |
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|
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func decoderErrf(tok LexerToken, str string, args ...interface{}) error { |
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return decoderErr(tok, fmt.Errorf(str, args...)) |
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} |
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// Decoder reads Value's off of a byte stream.
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type Decoder struct { |
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br *bufio.Reader |
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brNextLoc Location |
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|
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func isPunct(tok LexerToken, val string) bool { |
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return tok.Kind == LexerTokenKindPunctuation && tok.Value == val |
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unread []locatableRune |
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lastRead locatableRune |
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} |
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|
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func isTerm(tok LexerToken) bool { |
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return isPunct(tok, punctTerm) |
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} |
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|
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// decoder is currently only really used to namespace functions related to
|
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// decoding Graphs. It may later have actual fields added to it, such as for
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// options passed by the caller.
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type decoder struct{} |
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|
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// returned boolean value indicates if the token following the single token is a
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// term. If a term followed the first token then it is not included in the
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// returned leftover tokens.
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//
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// if termed is false then leftover tokens cannot be empty.
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func (d *decoder) parseSingleValue( |
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toks []LexerToken, |
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) ( |
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Value, []LexerToken, bool, error, |
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) { |
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|
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tok, rest := toks[0], toks[1:] |
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if len(rest) == 0 { |
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return ZeroValue, nil, false, decoderErrf(tok, "cannot be final token, possibly missing %q", punctTerm) |
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} |
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termed := isTerm(rest[0]) |
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if termed { |
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rest = rest[1:] |
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} |
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switch tok.Kind { |
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case LexerTokenKindName: |
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return Value{Name: &tok.Value, LexerToken: &tok}, rest, termed, nil |
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case LexerTokenKindNumber: |
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i, err := strconv.ParseInt(tok.Value, 10, 64) |
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if err != nil { |
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return ZeroValue, nil, false, decoderErrf(tok, "parsing %q as integer: %w", tok.Value, err) |
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} |
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|
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return Value{Number: &i, LexerToken: &tok}, rest, termed, nil |
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case LexerTokenKindPunctuation: |
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return ZeroValue, nil, false, decoderErrf(tok, "expected value, found punctuation %q", tok.Value) |
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default: |
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panic(fmt.Sprintf("unexpected token kind %q", tok.Kind)) |
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// NewDecoder returns a Decoder which will decode the given stream as a gg
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// formatted stream of a Values.
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func NewDecoder(r io.Reader) *Decoder { |
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return &Decoder{ |
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br: bufio.NewReader(r), |
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brNextLoc: Location{Row: 1, Col: 1}, |
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} |
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} |
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|
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func (d *decoder) parseOpenEdge( |
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toks []LexerToken, |
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) ( |
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*OpenEdge, []LexerToken, error, |
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) { |
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|
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if isPunct(toks[0], punctOpenTuple) { |
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return d.parseTuple(toks) |
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func (d *Decoder) readRune() (locatableRune, error) { |
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if len(d.unread) > 0 { |
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d.lastRead = d.unread[len(d.unread)-1] |
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d.unread = d.unread[:len(d.unread)-1] |
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return d.lastRead, nil |
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} |
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|
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var ( |
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val Value |
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termed bool |
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err error |
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) |
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switch { |
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case isPunct(toks[0], punctOpenGraph): |
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val, toks, termed, err = d.parseGraphValue(toks, true) |
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default: |
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val, toks, termed, err = d.parseSingleValue(toks) |
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} |
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loc := d.brNextLoc |
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r, _, err := d.br.ReadRune() |
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if err != nil { |
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return nil, nil, err |
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} |
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|
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if termed { |
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return graph.ValueOut[Value](ZeroValue, val), toks, nil |
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} |
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opTok, toks := toks[0], toks[1:] |
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if !isPunct(opTok, punctOp) { |
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return nil, nil, decoderErrf(opTok, "must be %q or %q", punctOp, punctTerm) |
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} |
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if len(toks) == 0 { |
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return nil, nil, decoderErrf(opTok, "%q cannot terminate an edge declaration", punctOp) |
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} |
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oe, toks, err := d.parseOpenEdge(toks) |
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if err != nil { |
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return nil, nil, err |
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} |
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oe = graph.TupleOut[Value](val, oe) |
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return oe, toks, nil |
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} |
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func (d *decoder) parseTuple( |
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toks []LexerToken, |
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) ( |
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*OpenEdge, []LexerToken, error, |
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) { |
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openTok, toks := toks[0], toks[1:] |
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var edges []*OpenEdge |
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for { |
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if len(toks) == 0 { |
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return nil, nil, decoderErrf(openTok, "no matching %q", punctCloseTuple) |
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} else if isPunct(toks[0], punctCloseTuple) { |
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toks = toks[1:] |
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break |
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} |
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var ( |
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oe *OpenEdge |
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err error |
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) |
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oe, toks, err = d.parseOpenEdge(toks) |
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if err != nil { |
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return nil, nil, err |
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} |
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edges = append(edges, oe) |
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} |
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// this is a quirk of the syntax, _technically_ a tuple doesn't need a
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// term after it, since it can't be used as an edge value, and so
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// nothing can come after it in the chain.
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if len(toks) > 0 && isTerm(toks[0]) { |
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toks = toks[1:] |
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} |
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return graph.TupleOut[Value](ZeroValue, edges...), toks, nil |
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} |
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|
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// returned boolean value indicates if the token following the graph is a term.
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// If a term followed the first token then it is not included in the returned
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// leftover tokens.
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//
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// if termed is false then leftover tokens cannot be empty.
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func (d *decoder) parseGraphValue( |
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toks []LexerToken, expectWrappers bool, |
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) ( |
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Value, []LexerToken, bool, error, |
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) { |
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|
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var openTok LexerToken |
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if expectWrappers { |
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openTok, toks = toks[0], toks[1:] |
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} |
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g := new(Graph) |
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for { |
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if len(toks) == 0 { |
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if !expectWrappers { |
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break |
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} |
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return ZeroValue, nil, false, decoderErrf(openTok, "no matching %q", punctCloseGraph) |
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|
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} else if closingTok := toks[0]; isPunct(closingTok, punctCloseGraph) { |
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if !expectWrappers { |
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return ZeroValue, nil, false, decoderErrf(closingTok, "unexpected %q", punctCloseGraph) |
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} |
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toks = toks[1:] |
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if len(toks) == 0 { |
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return ZeroValue, nil, false, decoderErrf(closingTok, "cannot be final token, possibly missing %q", punctTerm) |
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} |
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break |
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} |
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var err error |
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if g, toks, err = d.parseValIn(g, toks); err != nil { |
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return ZeroValue, nil, false, err |
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} |
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} |
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val := Value{Graph: g} |
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if !expectWrappers { |
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return val, toks, true, nil |
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return d.lastRead, err |
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} |
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val.LexerToken = &openTok |
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termed := isTerm(toks[0]) |
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if termed { |
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toks = toks[1:] |
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if r == '\n' { |
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d.brNextLoc.Row++ |
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d.brNextLoc.Col = 1 |
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} else { |
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d.brNextLoc.Col++ |
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} |
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return val, toks, termed, nil |
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d.lastRead = locatableRune{loc, r} |
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return d.lastRead, nil |
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} |
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func (d *decoder) parseValIn(into *Graph, toks []LexerToken) (*Graph, []LexerToken, error) { |
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if len(toks) == 0 { |
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return into, nil, nil |
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} else if len(toks) < 3 { |
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return nil, nil, decoderErrf(toks[0], `must be of the form "<name> = ..."`) |
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func (d *Decoder) unreadRune(lr locatableRune) { |
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if d.lastRead != lr { |
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panic(fmt.Sprintf( |
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"unreading rune %#v, but last read rune was %#v", lr, d.lastRead, |
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)) |
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} |
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dst := toks[0] |
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eq := toks[1] |
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toks = toks[2:] |
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if dst.Kind != LexerTokenKindName { |
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return nil, nil, decoderErrf(dst, "must be a name") |
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} else if !isPunct(eq, punctAssign) { |
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return nil, nil, decoderErrf(eq, "must be %q", punctAssign) |
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} |
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oe, toks, err := d.parseOpenEdge(toks) |
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if err != nil { |
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return nil, nil, err |
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} |
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dstVal := Value{Name: &dst.Value, LexerToken: &dst} |
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return into.AddValueIn(dstVal, oe), toks, nil |
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d.unread = append(d.unread, lr) |
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} |
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func (d *decoder) readAllTokens(lexer Lexer) ([]LexerToken, error) { |
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var toks []LexerToken |
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for { |
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tok, err := lexer.Next() |
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|
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if errors.Is(err, io.EOF) { |
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break |
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|
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} else if err != nil { |
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return nil, fmt.Errorf("reading next token: %w", err) |
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} |
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toks = append(toks, tok) |
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func (d *Decoder) nextLoc() Location { |
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if len(d.unread) > 0 { |
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return d.unread[len(d.unread)-1].Location |
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} |
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|
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return toks, nil |
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return d.brNextLoc |
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} |
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|
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func (d *decoder) decode(lexer Lexer) (*Graph, error) { |
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toks, err := d.readAllTokens(lexer) |
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|
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if err != nil { |
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return nil, err |
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} |
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|
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val, _, _, err := d.parseGraphValue(toks, false) |
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|
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if err != nil { |
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return nil, err |
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} |
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return val.Graph, nil |
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} |
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|
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// DecodeLexer reads lexigraphical tokens from the given Lexer and uses them to
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// construct a Graph according to the rules of the gg file format. DecodeLexer
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// will only return an error if there is a non-EOF file returned from the Lexer,
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// or the tokens read cannot be used to construct a valid Graph.
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func DecodeLexer(lexer Lexer) (*Graph, error) { |
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decoder := &decoder{} |
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return decoder.decode(lexer) |
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} |
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|
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func DecodeSingleValueFromLexer(lexer Lexer) (Value, error) { |
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decoder := &decoder{} |
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|
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toks, err := decoder.readAllTokens(lexer) |
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|
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if err != nil { |
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return ZeroValue, err |
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} |
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|
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val, _, _, err := decoder.parseSingleValue(toks) |
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|
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return val, err |
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// Next returns the next top-level value in the stream, or io.EOF.
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func (d *Decoder) Next() (Value, error) { |
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return topLevelTerm.decodeFn(d) |
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} |
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|
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@ -1,149 +0,0 @@ |
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package gg |
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|
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import ( |
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"strconv" |
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"testing" |
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|
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"github.com/stretchr/testify/assert" |
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|
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"github.com/mediocregopher/ginger/graph" |
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) |
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|
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func TestDecoder(t *testing.T) { |
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zeroGraph := new(Graph) |
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|
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i := func(i int64) Value { |
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return Value{Number: &i} |
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} |
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|
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n := func(n string) Value { |
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return Value{Name: &n} |
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} |
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|
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vOut := func(edgeVal, val Value) *OpenEdge { |
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return graph.ValueOut(edgeVal, val) |
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} |
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|
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tOut := func(edgeVal Value, ins ...*OpenEdge) *OpenEdge { |
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return graph.TupleOut(edgeVal, ins...) |
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} |
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|
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tests := []struct { |
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in string |
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exp *Graph |
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}{ |
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{ |
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in: "", |
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exp: zeroGraph, |
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}, |
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{ |
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in: "out = 1;", |
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exp: zeroGraph.AddValueIn(n("out"), vOut(ZeroValue, i(1))), |
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}, |
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{ |
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in: "out = incr < 1;", |
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exp: zeroGraph.AddValueIn(n("out"), vOut(n("incr"), i(1))), |
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}, |
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{ |
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in: "out = a < b < 1;", |
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exp: zeroGraph.AddValueIn( |
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n("out"), |
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tOut( |
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n("a"), |
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vOut(n("b"), |
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i(1)), |
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), |
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), |
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}, |
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{ |
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in: "out = a < b < (1; c < 2; d < e < 3;);", |
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exp: zeroGraph.AddValueIn( |
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n("out"), |
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tOut( |
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n("a"), |
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tOut( |
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n("b"), |
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vOut(ZeroValue, i(1)), |
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vOut(n("c"), i(2)), |
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tOut( |
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n("d"), |
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vOut(n("e"), i(3)), |
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), |
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), |
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), |
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), |
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}, |
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{ |
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in: "out = a < b < (1; c < (d < 2; 3;); );", |
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exp: zeroGraph.AddValueIn( |
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n("out"), |
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tOut( |
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n("a"), |
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tOut( |
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n("b"), |
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vOut(ZeroValue, i(1)), |
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tOut( |
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n("c"), |
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vOut(n("d"), i(2)), |
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vOut(ZeroValue, i(3)), |
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), |
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), |
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), |
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), |
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}, |
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{ |
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in: "out = { a = 1; b = c < d < 2; };", |
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exp: zeroGraph.AddValueIn( |
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n("out"), |
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vOut( |
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ZeroValue, |
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Value{Graph: zeroGraph. |
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AddValueIn(n("a"), vOut(ZeroValue, i(1))). |
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AddValueIn( |
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n("b"), |
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tOut( |
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n("c"), |
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vOut(n("d"), i(2)), |
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), |
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), |
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}, |
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), |
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), |
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}, |
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{ |
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in: "out = a < { b = 1; } < 2;", |
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exp: zeroGraph.AddValueIn( |
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n("out"), |
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tOut( |
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n("a"), |
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vOut( |
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Value{Graph: zeroGraph. |
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AddValueIn(n("b"), vOut(ZeroValue, i(1))), |
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}, |
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i(2), |
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), |
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), |
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), |
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}, |
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{ |
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in: "a = 1; b = 2;", |
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exp: zeroGraph. |
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AddValueIn(n("a"), vOut(ZeroValue, i(1))). |
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AddValueIn(n("b"), vOut(ZeroValue, i(2))), |
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}, |
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} |
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|
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for i, test := range tests { |
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t.Run(strconv.Itoa(i), func(t *testing.T) { |
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|
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r := &mockReader{body: []byte(test.in)} |
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lexer := NewLexer(r) |
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|
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got, err := DecodeLexer(lexer) |
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assert.NoError(t, err) |
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assert.True(t, got.Equal(test.exp), "\nexp:%v\ngot:%v", test.exp, got) |
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|
||||
}) |
||||
} |
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} |
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@ -0,0 +1,23 @@ |
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<digit> ::= "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" |
||||
<positive-number> ::= <digit>+ |
||||
<negative-number> ::= "-" <positive-number> |
||||
<number> ::= <negative-number> | <positive-number> |
||||
|
||||
<name> ::= (<letter> | <mark>) (<letter> | <mark> | <digit>)* |
||||
|
||||
<tuple> ::= "(" <tuple-tail> |
||||
<tuple-tail> ::= ")" | <tuple-open-edge> |
||||
<tuple-open-edge> ::= <value> <tuple-open-edge-value-tail> |
||||
| <tuple> <tuple-open-edge-tail> |
||||
<tuple-open-edge-tail> ::= ")" | "," <tuple-tail> |
||||
<tuple-open-edge-value-tail> ::= <tuple-open-edge-tail> | "<" <tuple-open-edge> |
||||
|
||||
<graph> ::= "{" <graph-tail> |
||||
<graph-tail> ::= "}" | <name> "=" <graph-open-edge> |
||||
<graph-open-edge> ::= <value> <graph-open-edge-value-tail> |
||||
| <tuple> <graph-open-edge-tail> |
||||
<graph-open-edge-tail> ::= "}" | ";" <graph-tail> |
||||
<graph-open-edge-value-tail> ::= <graph-open-edge-tail> | "<" <graph-open-edge> |
||||
|
||||
<value> ::= <name> | <number> | <graph> |
||||
<gg> ::= <eof> | <value> <gg> |
||||
@ -1,292 +0,0 @@ |
||||
package gg |
||||
|
||||
import ( |
||||
"bufio" |
||||
"fmt" |
||||
"io" |
||||
"strings" |
||||
"unicode" |
||||
) |
||||
|
||||
// LexerLocation describes the location in a file where a particular token was
|
||||
// parsed from.
|
||||
type LexerLocation struct { |
||||
Row, Col int |
||||
} |
||||
|
||||
func (l LexerLocation) String() string { |
||||
return fmt.Sprintf("%d:%d", l.Row, l.Col) |
||||
} |
||||
|
||||
// LexerError is returned by Lexer when an unexpected error occurs parsing a
|
||||
// stream of LexerTokens.
|
||||
type LexerError struct { |
||||
Err error |
||||
|
||||
Location LexerLocation |
||||
} |
||||
|
||||
func (e *LexerError) Error() string { |
||||
return fmt.Sprintf("%s: %s", e.Location.String(), e.Err.Error()) |
||||
} |
||||
|
||||
func (e *LexerError) Unwrap() error { |
||||
return e.Err |
||||
} |
||||
|
||||
// LexerTokenKind enumerates the different kinds of LexerToken there can be.
|
||||
type LexerTokenKind string |
||||
|
||||
// Enumeration of LexerTokenKinds.
|
||||
const ( |
||||
LexerTokenKindName LexerTokenKind = "name" |
||||
LexerTokenKindNumber LexerTokenKind = "number" |
||||
LexerTokenKindPunctuation LexerTokenKind = "punctuation" |
||||
) |
||||
|
||||
// LexerToken describes a lexigraphical token which is used when deserializing
|
||||
// Graphs.
|
||||
type LexerToken struct { |
||||
Kind LexerTokenKind |
||||
Value string // never empty string
|
||||
|
||||
Location LexerLocation |
||||
} |
||||
|
||||
func (t LexerToken) errPrefix() string { |
||||
return fmt.Sprintf("%s: at %q", t.Location.String(), t.Value) |
||||
} |
||||
|
||||
// Lexer is used to parse a string stream into a sequence of tokens which can
|
||||
// then be parsed by a Parser.
|
||||
type Lexer interface { |
||||
|
||||
// Next will return a LexerToken or a LexerError. io.EOF (wrapped in a
|
||||
// LexerError) is returned if the stream being read from is finished.
|
||||
Next() (LexerToken, error) |
||||
} |
||||
|
||||
type lexer struct { |
||||
r *bufio.Reader |
||||
stringBuilder *strings.Builder |
||||
err *LexerError |
||||
|
||||
// these fields are only needed to keep track of the current "cursor"
|
||||
// position when reading.
|
||||
lastRow, lastCol int |
||||
prevRune rune |
||||
} |
||||
|
||||
// NewLexer wraps the io.Reader in a Lexer, which will read the io.Reader as a
|
||||
// sequence of utf-8 characters and parse it into a sequence of LexerTokens.
|
||||
func NewLexer(r io.Reader) Lexer { |
||||
return &lexer{ |
||||
r: bufio.NewReader(r), |
||||
lastRow: 0, |
||||
lastCol: -1, |
||||
stringBuilder: new(strings.Builder), |
||||
} |
||||
} |
||||
|
||||
// nextRowCol returns the row and column number which the next rune in the
|
||||
// stream would be at.
|
||||
func (l *lexer) nextRowCol() (int, int) { |
||||
|
||||
if l.prevRune == '\n' { |
||||
return l.lastRow + 1, 0 |
||||
} |
||||
|
||||
return l.lastRow, l.lastCol + 1 |
||||
} |
||||
|
||||
func (l *lexer) fmtErr(err error) *LexerError { |
||||
|
||||
row, col := l.nextRowCol() |
||||
|
||||
return &LexerError{ |
||||
Err: err, |
||||
Location: LexerLocation{ |
||||
Row: row, |
||||
Col: col, |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func (l *lexer) fmtErrf(str string, args ...interface{}) *LexerError { |
||||
return l.fmtErr(fmt.Errorf(str, args...)) |
||||
} |
||||
|
||||
// discardRune must _always_ be called only after peekRune.
|
||||
func (l *lexer) discardRune() { |
||||
|
||||
r, _, err := l.r.ReadRune() |
||||
|
||||
if err != nil { |
||||
panic(err) |
||||
} |
||||
|
||||
l.lastRow, l.lastCol = l.nextRowCol() |
||||
l.prevRune = r |
||||
} |
||||
|
||||
func (l *lexer) peekRune() (rune, error) { |
||||
|
||||
r, _, err := l.r.ReadRune() |
||||
|
||||
if err != nil { |
||||
return '0', err |
||||
|
||||
} else if err := l.r.UnreadRune(); err != nil { |
||||
|
||||
// since the most recent operation on the bufio.Reader was a ReadRune,
|
||||
// UnreadRune should never return an error
|
||||
panic(err) |
||||
} |
||||
|
||||
return r, nil |
||||
} |
||||
|
||||
// readWhile reads runes until the given predicate returns false, and returns a
|
||||
// LexerToken of the given kind whose Value is comprised of all runes which
|
||||
// returned true.
|
||||
//
|
||||
// If an error is encountered then both the token (or what's been parsed of it
|
||||
// so far) and the error are returned.
|
||||
func (l *lexer) readWhile( |
||||
kind LexerTokenKind, pred func(rune) bool, |
||||
) ( |
||||
LexerToken, *LexerError, |
||||
) { |
||||
|
||||
row, col := l.nextRowCol() |
||||
|
||||
l.stringBuilder.Reset() |
||||
|
||||
var lexErr *LexerError |
||||
|
||||
for { |
||||
|
||||
r, err := l.peekRune() |
||||
|
||||
if err != nil { |
||||
lexErr = l.fmtErrf("peeking next character: %w", err) |
||||
break |
||||
|
||||
} else if !pred(r) { |
||||
break |
||||
} |
||||
|
||||
l.stringBuilder.WriteRune(r) |
||||
|
||||
l.discardRune() |
||||
} |
||||
|
||||
return LexerToken{ |
||||
Kind: kind, |
||||
Value: l.stringBuilder.String(), |
||||
Location: LexerLocation{ |
||||
Row: row, Col: col, |
||||
}, |
||||
}, lexErr |
||||
} |
||||
|
||||
// we only support base-10 integers at the moment.
|
||||
func isNumber(r rune) bool { |
||||
return r == '-' || ('0' <= r && r <= '9') |
||||
} |
||||
|
||||
// next can return a token, an error, or both. If an error is returned then no
|
||||
// further calls to next should occur.
|
||||
func (l *lexer) next() (LexerToken, *LexerError) { |
||||
|
||||
for { |
||||
|
||||
r, err := l.peekRune() |
||||
|
||||
if err != nil { |
||||
return LexerToken{}, l.fmtErrf("peeking next character: %w", err) |
||||
} |
||||
|
||||
switch { |
||||
|
||||
case r == '*': // comment
|
||||
|
||||
// comments are everything up until a newline
|
||||
_, err := l.readWhile("", func(r rune) bool { |
||||
return r != '\n' |
||||
}) |
||||
|
||||
if err != nil { |
||||
return LexerToken{}, err |
||||
} |
||||
|
||||
// terminating newline will be discarded on next loop
|
||||
|
||||
case r == '"' || r == '`': |
||||
|
||||
// reserve double-quote and backtick for string parsing.
|
||||
l.discardRune() |
||||
return LexerToken{}, l.fmtErrf("string parsing not yet implemented") |
||||
|
||||
case unicode.IsLetter(r): |
||||
// letters denote the start of a name
|
||||
|
||||
return l.readWhile(LexerTokenKindName, func(r rune) bool { |
||||
|
||||
if unicode.In(r, unicode.Letter, unicode.Number, unicode.Mark) { |
||||
return true |
||||
} |
||||
|
||||
if r == '-' { |
||||
return true |
||||
} |
||||
|
||||
return false |
||||
}) |
||||
|
||||
case isNumber(r): |
||||
return l.readWhile(LexerTokenKindNumber, isNumber) |
||||
|
||||
case unicode.IsPunct(r) || unicode.IsSymbol(r): |
||||
// symbols are also considered punctuation
|
||||
|
||||
l.discardRune() |
||||
|
||||
return LexerToken{ |
||||
Kind: LexerTokenKindPunctuation, |
||||
Value: string(r), |
||||
Location: LexerLocation{ |
||||
Row: l.lastRow, |
||||
Col: l.lastCol, |
||||
}, |
||||
}, nil |
||||
|
||||
case unicode.IsSpace(r): |
||||
l.discardRune() |
||||
|
||||
default: |
||||
return LexerToken{}, l.fmtErrf("unexpected character %q", r) |
||||
} |
||||
|
||||
} |
||||
} |
||||
|
||||
func (l *lexer) Next() (LexerToken, error) { |
||||
|
||||
if l.err != nil { |
||||
return LexerToken{}, l.err |
||||
} |
||||
|
||||
tok, err := l.next() |
||||
|
||||
if err != nil { |
||||
|
||||
l.err = err |
||||
|
||||
if tok.Kind == "" { |
||||
return LexerToken{}, l.err |
||||
} |
||||
} |
||||
|
||||
return tok, nil |
||||
} |
||||
@ -1,150 +0,0 @@ |
||||
package gg |
||||
|
||||
import ( |
||||
"errors" |
||||
"strconv" |
||||
"strings" |
||||
"testing" |
||||
|
||||
"github.com/stretchr/testify/assert" |
||||
) |
||||
|
||||
func TestLexer(t *testing.T) { |
||||
|
||||
expErr := errors.New("eof") |
||||
|
||||
tests := []struct { |
||||
in string |
||||
exp []LexerToken |
||||
}{ |
||||
{in: "", exp: []LexerToken{}}, |
||||
{in: "* fooo\n", exp: []LexerToken{}}, |
||||
{ |
||||
in: "foo", |
||||
exp: []LexerToken{ |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "foo", |
||||
Location: LexerLocation{Row: 0, Col: 0}, |
||||
}, |
||||
}, |
||||
}, |
||||
{ |
||||
in: "foo bar\nf-o f0O Foo", |
||||
exp: []LexerToken{ |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "foo", |
||||
Location: LexerLocation{Row: 0, Col: 0}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "bar", |
||||
Location: LexerLocation{Row: 0, Col: 4}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "f-o", |
||||
Location: LexerLocation{Row: 1, Col: 0}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "f0O", |
||||
Location: LexerLocation{Row: 1, Col: 4}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindName, |
||||
Value: "Foo", |
||||
Location: LexerLocation{Row: 1, Col: 8}, |
||||
}, |
||||
}, |
||||
}, |
||||
{ |
||||
in: "1 100 -100", |
||||
exp: []LexerToken{ |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "1", |
||||
Location: LexerLocation{Row: 0, Col: 0}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "100", |
||||
Location: LexerLocation{Row: 0, Col: 2}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "-100", |
||||
Location: LexerLocation{Row: 0, Col: 6}, |
||||
}, |
||||
}, |
||||
}, |
||||
{ |
||||
in: "1<2!-3 ()", |
||||
exp: []LexerToken{ |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "1", |
||||
Location: LexerLocation{Row: 0, Col: 0}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindPunctuation, |
||||
Value: "<", |
||||
Location: LexerLocation{Row: 0, Col: 1}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "2", |
||||
Location: LexerLocation{Row: 0, Col: 2}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindPunctuation, |
||||
Value: "!", |
||||
Location: LexerLocation{Row: 0, Col: 3}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindNumber, |
||||
Value: "-3", |
||||
Location: LexerLocation{Row: 0, Col: 4}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindPunctuation, |
||||
Value: "(", |
||||
Location: LexerLocation{Row: 0, Col: 7}, |
||||
}, |
||||
{ |
||||
Kind: LexerTokenKindPunctuation, |
||||
Value: ")", |
||||
Location: LexerLocation{Row: 0, Col: 8}, |
||||
}, |
||||
}, |
||||
}, |
||||
} |
||||
|
||||
for i, test := range tests { |
||||
t.Run(strconv.Itoa(i), func(t *testing.T) { |
||||
|
||||
lexer := NewLexer(&mockReader{body: []byte(test.in), err: expErr}) |
||||
|
||||
for i := range test.exp { |
||||
tok, err := lexer.Next() |
||||
assert.NoError(t, err) |
||||
assert.Equal(t, test.exp[i], tok, "test.exp[%d]", i) |
||||
} |
||||
|
||||
tok, err := lexer.Next() |
||||
assert.ErrorIs(t, err, expErr) |
||||
assert.Equal(t, LexerToken{}, tok) |
||||
|
||||
lexErr := new(LexerError) |
||||
assert.True(t, errors.As(err, &lexErr)) |
||||
|
||||
inParts := strings.Split(test.in, "\n") |
||||
|
||||
assert.ErrorIs(t, lexErr, expErr) |
||||
assert.Equal(t, lexErr.Location.Row, len(inParts)-1) |
||||
assert.Equal(t, lexErr.Location.Col, len(inParts[len(inParts)-1])) |
||||
}) |
||||
} |
||||
|
||||
} |
||||
@ -0,0 +1,36 @@ |
||||
package gg |
||||
|
||||
import "fmt" |
||||
|
||||
// Location indicates a position in a stream of bytes identified by column
|
||||
// within newline-separated rows.
|
||||
type Location struct { |
||||
Row, Col int |
||||
} |
||||
|
||||
func (l Location) errf(str string, args ...any) LocatedError { |
||||
return LocatedError{l, fmt.Errorf(str, args...)} |
||||
} |
||||
|
||||
func (l Location) locate() Location { return l } |
||||
|
||||
// LocatedError is an error related to a specific point within a decode gg
|
||||
// stream.
|
||||
type LocatedError struct { |
||||
Location |
||||
Err error |
||||
} |
||||
|
||||
func (e LocatedError) Error() string { |
||||
return fmt.Sprintf("%d:%d: %v", e.Row, e.Col, e.Err) |
||||
} |
||||
|
||||
type locatableRune struct { |
||||
Location |
||||
r rune |
||||
} |
||||
|
||||
type locatableString struct { |
||||
Location |
||||
str string |
||||
} |
||||
@ -0,0 +1,508 @@ |
||||
package gg |
||||
|
||||
import ( |
||||
"errors" |
||||
"fmt" |
||||
"io" |
||||
"strconv" |
||||
"strings" |
||||
"unicode" |
||||
|
||||
"github.com/mediocregopher/ginger/graph" |
||||
"golang.org/x/exp/slices" |
||||
) |
||||
|
||||
var ( |
||||
errNoMatch = errors.New("not found") |
||||
) |
||||
|
||||
type stringerFn func() string |
||||
|
||||
func (fn stringerFn) String() string { |
||||
return fn() |
||||
} |
||||
|
||||
type stringerStr string |
||||
|
||||
func (str stringerStr) String() string { |
||||
return string(str) |
||||
} |
||||
|
||||
type term[T any] struct { |
||||
name fmt.Stringer |
||||
decodeFn func(d *Decoder) (T, error) |
||||
} |
||||
|
||||
func (t term[T]) String() string { |
||||
return t.name.String() |
||||
} |
||||
|
||||
func firstOf[T any](terms ...*term[T]) *term[T] { |
||||
if len(terms) < 2 { |
||||
panic("firstOfTerms requires at least 2 terms") |
||||
} |
||||
|
||||
return &term[T]{ |
||||
name: stringerFn(func() string { |
||||
descrs := make([]string, len(terms)) |
||||
for i := range terms { |
||||
descrs[i] = terms[i].String() |
||||
} |
||||
return strings.Join(descrs, " or ") |
||||
}), |
||||
decodeFn: func(d *Decoder) (T, error) { |
||||
var zero T |
||||
for _, t := range terms { |
||||
v, err := t.decodeFn(d) |
||||
if errors.Is(err, errNoMatch) { |
||||
continue |
||||
} else if err != nil { |
||||
return zero, err |
||||
} |
||||
|
||||
return v, nil |
||||
} |
||||
|
||||
return zero, errNoMatch |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func seq[Ta, Tb, Tc any]( |
||||
name fmt.Stringer, |
||||
termA *term[Ta], |
||||
termB *term[Tb], |
||||
fn func(Ta, Tb) Tc, |
||||
) *term[Tc] { |
||||
return &term[Tc]{ |
||||
name: name, |
||||
decodeFn: func(d *Decoder) (Tc, error) { |
||||
var zero Tc |
||||
|
||||
va, err := termA.decodeFn(d) |
||||
if err != nil { |
||||
return zero, err |
||||
} |
||||
|
||||
vb, err := termB.decodeFn(d) |
||||
if errors.Is(err, errNoMatch) { |
||||
return zero, d.nextLoc().errf("expected %v", termB) |
||||
} else if err != nil { |
||||
return zero, err |
||||
} |
||||
|
||||
return fn(va, vb), nil |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func prefixed[Ta, Tb any](termA *term[Ta], termB *term[Tb]) *term[Tb] { |
||||
return seq(termA, termA, termB, func(_ Ta, b Tb) Tb { |
||||
return b |
||||
}) |
||||
} |
||||
|
||||
func prefixIgnored[Ta, Tb any](termA *term[Ta], termB *term[Tb]) *term[Tb] { |
||||
return &term[Tb]{ |
||||
name: termB, |
||||
decodeFn: func(d *Decoder) (Tb, error) { |
||||
var zero Tb |
||||
if _, err := termA.decodeFn(d); err != nil { |
||||
return zero, err |
||||
} |
||||
return termB.decodeFn(d) |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func suffixIgnored[Ta, Tb any]( |
||||
termA *term[Ta], termB *term[Tb], |
||||
) *term[Ta] { |
||||
return seq(termA, termA, termB, func(a Ta, _ Tb) Ta { |
||||
return a |
||||
}) |
||||
} |
||||
|
||||
func oneOrMore[T any](t *term[T]) *term[[]T] { |
||||
return &term[[]T]{ |
||||
name: stringerFn(func() string { |
||||
return fmt.Sprintf("one or more %v", t) |
||||
}), |
||||
decodeFn: func(d *Decoder) ([]T, error) { |
||||
var vv []T |
||||
for { |
||||
v, err := t.decodeFn(d) |
||||
if errors.Is(err, errNoMatch) { |
||||
break |
||||
} else if err != nil { |
||||
return nil, err |
||||
} |
||||
|
||||
vv = append(vv, v) |
||||
} |
||||
|
||||
if len(vv) == 0 { |
||||
return nil, errNoMatch |
||||
} |
||||
|
||||
return vv, nil |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func zeroOrMore[T any](t *term[T]) *term[[]T] { |
||||
return &term[[]T]{ |
||||
name: stringerFn(func() string { |
||||
return fmt.Sprintf("zero or more %v", t) |
||||
}), |
||||
decodeFn: func(d *Decoder) ([]T, error) { |
||||
var vv []T |
||||
for { |
||||
v, err := t.decodeFn(d) |
||||
if errors.Is(err, errNoMatch) { |
||||
break |
||||
} else if err != nil { |
||||
return nil, err |
||||
} |
||||
|
||||
vv = append(vv, v) |
||||
} |
||||
|
||||
return vv, nil |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func mapTerm[Ta, Tb any]( |
||||
name fmt.Stringer, t *term[Ta], fn func(Ta) Tb, |
||||
) *term[Tb] { |
||||
return &term[Tb]{ |
||||
name: name, |
||||
decodeFn: func(d *Decoder) (Tb, error) { |
||||
var zero Tb |
||||
va, err := t.decodeFn(d) |
||||
if err != nil { |
||||
return zero, err |
||||
} |
||||
return fn(va), nil |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func runePredTerm( |
||||
name fmt.Stringer, pred func(rune) bool, |
||||
) *term[locatableRune] { |
||||
return &term[locatableRune]{ |
||||
name: name, |
||||
decodeFn: func(d *Decoder) (locatableRune, error) { |
||||
lr, err := d.readRune() |
||||
if errors.Is(err, io.EOF) { |
||||
return locatableRune{}, errNoMatch |
||||
} else if err != nil { |
||||
return locatableRune{}, err |
||||
} |
||||
|
||||
if !pred(lr.r) { |
||||
d.unreadRune(lr) |
||||
return locatableRune{}, errNoMatch |
||||
} |
||||
|
||||
return lr, nil |
||||
}, |
||||
} |
||||
} |
||||
|
||||
func runeTerm(r rune) *term[locatableRune] { |
||||
return runePredTerm( |
||||
stringerStr(fmt.Sprintf("'%c'", r)), |
||||
func(r2 rune) bool { return r2 == r }, |
||||
) |
||||
} |
||||
|
||||
func locatableRunesToString(rr []locatableRune) string { |
||||
str := make([]rune, len(rr)) |
||||
for i := range rr { |
||||
str[i] = rr[i].r |
||||
} |
||||
return string(str) |
||||
} |
||||
|
||||
func runesToStringTerm( |
||||
t *term[[]locatableRune], |
||||
) *term[locatableString] { |
||||
return mapTerm( |
||||
t, t, func(rr []locatableRune) locatableString { |
||||
return locatableString{rr[0].locate(), locatableRunesToString(rr)} |
||||
}, |
||||
) |
||||
} |
||||
|
||||
func discard[T any](t *term[T]) *term[struct{}] { |
||||
return mapTerm(t, t, func(_ T) struct{} { return struct{}{} }) |
||||
} |
||||
|
||||
var ( |
||||
notNewlineTerm = runePredTerm( |
||||
stringerStr("not-newline"), |
||||
func(r rune) bool { return r != '\n' }, |
||||
) |
||||
|
||||
commentTerm = prefixed( |
||||
prefixed(runeTerm('*'), zeroOrMore(notNewlineTerm)), |
||||
runeTerm('\n'), |
||||
) |
||||
|
||||
whitespaceTerm = zeroOrMore(firstOf( |
||||
discard(runePredTerm(stringerStr("whitespace"), unicode.IsSpace)), |
||||
discard(commentTerm), |
||||
)) |
||||
) |
||||
|
||||
func trimmedTerm[T any](t *term[T]) *term[T] { |
||||
t = prefixIgnored(whitespaceTerm, t) |
||||
t = suffixIgnored(t, whitespaceTerm) |
||||
return t |
||||
} |
||||
|
||||
func trimmedRuneTerm(r rune) *term[locatableRune] { |
||||
return trimmedTerm(runeTerm(r)) |
||||
} |
||||
|
||||
var ( |
||||
digitTerm = runePredTerm( |
||||
stringerStr("digit"), |
||||
func(r rune) bool { return '0' <= r && r <= '9' }, |
||||
) |
||||
|
||||
positiveNumberTerm = runesToStringTerm(oneOrMore(digitTerm)) |
||||
|
||||
negativeNumberTerm = seq( |
||||
stringerStr("negative-number"), |
||||
runeTerm('-'), |
||||
positiveNumberTerm, |
||||
func(neg locatableRune, posNum locatableString) locatableString { |
||||
return locatableString{neg.locate(), string(neg.r) + posNum.str} |
||||
}, |
||||
) |
||||
|
||||
numberTerm = mapTerm( |
||||
stringerStr("number"), |
||||
firstOf(negativeNumberTerm, positiveNumberTerm), |
||||
func(str locatableString) Value { |
||||
i, err := strconv.ParseInt(str.str, 10, 64) |
||||
if err != nil { |
||||
panic(fmt.Errorf("parsing %q as int: %w", str, err)) |
||||
} |
||||
|
||||
return Value{Number: &i, Location: str.locate()} |
||||
}, |
||||
) |
||||
) |
||||
|
||||
var ( |
||||
letterTerm = runePredTerm( |
||||
stringerStr("letter"), |
||||
func(r rune) bool { |
||||
return unicode.In(r, unicode.Letter, unicode.Mark) |
||||
}, |
||||
) |
||||
|
||||
letterTailTerm = zeroOrMore(firstOf(letterTerm, digitTerm)) |
||||
|
||||
nameTerm = seq( |
||||
stringerStr("name"), |
||||
letterTerm, |
||||
letterTailTerm, |
||||
func(head locatableRune, tail []locatableRune) Value { |
||||
name := string(head.r) + locatableRunesToString(tail) |
||||
return Value{Name: &name, Location: head.locate()} |
||||
}, |
||||
) |
||||
) |
||||
|
||||
func openEdgeIntoValue(val Value, oe *OpenEdge) *OpenEdge { |
||||
switch { |
||||
case oe == nil: |
||||
return graph.ValueOut(None, val) |
||||
case !oe.EdgeValue().Valid: |
||||
return oe.WithEdgeValue(Some(val)) |
||||
default: |
||||
return graph.TupleOut(Some(val), oe) |
||||
} |
||||
} |
||||
|
||||
var graphTerm, valueTerm = func() (*term[Value], *term[Value]) { |
||||
type tupleState struct { |
||||
ins []*OpenEdge |
||||
oe *OpenEdge |
||||
} |
||||
|
||||
type graphState struct { |
||||
g *Graph |
||||
oe *OpenEdge |
||||
} |
||||
|
||||
var ( |
||||
rightParenthesis = trimmedRuneTerm(')') |
||||
tupleEndTerm = mapTerm( |
||||
rightParenthesis, |
||||
rightParenthesis, |
||||
func(lr locatableRune) tupleState { |
||||
// if ')', then map that to an empty state. This acts as a
|
||||
// sentinel value to indicate "end of tuple".
|
||||
return tupleState{} |
||||
}, |
||||
) |
||||
|
||||
rightCurlyBrace = trimmedRuneTerm('}') |
||||
graphEndTerm = mapTerm( |
||||
rightCurlyBrace, |
||||
rightCurlyBrace, |
||||
func(lr locatableRune) graphState { |
||||
// if '}', then map that to an empty state. This acts as a
|
||||
// sentinel value to indicate "end of graph".
|
||||
return graphState{} |
||||
}, |
||||
) |
||||
) |
||||
|
||||
var ( |
||||
// pre-define these, and then fill in the pointers after, in order to
|
||||
// deal with recursive dependencies between them.
|
||||
valueTerm = new(term[Value]) |
||||
|
||||
tupleTerm = new(term[*OpenEdge]) |
||||
tupleTailTerm = new(term[tupleState]) |
||||
tupleOpenEdgeTerm = new(term[tupleState]) |
||||
tupleOpenEdgeTailTerm = new(term[tupleState]) |
||||
tupleOpenEdgeValueTailTerm = new(term[tupleState]) |
||||
|
||||
graphTerm = new(term[Value]) |
||||
graphTailTerm = new(term[graphState]) |
||||
graphOpenEdgeTerm = new(term[graphState]) |
||||
graphOpenEdgeTailTerm = new(term[graphState]) |
||||
graphOpenEdgeValueTailTerm = new(term[graphState]) |
||||
) |
||||
|
||||
*tupleTerm = *seq( |
||||
stringerStr("tuple"), |
||||
trimmedRuneTerm('('), |
||||
tupleTailTerm, |
||||
func(lr locatableRune, ts tupleState) *OpenEdge { |
||||
slices.Reverse(ts.ins) |
||||
return graph.TupleOut(None, ts.ins...) |
||||
}, |
||||
) |
||||
|
||||
*tupleTailTerm = *firstOf( |
||||
tupleEndTerm, |
||||
mapTerm( |
||||
tupleOpenEdgeTerm, |
||||
tupleOpenEdgeTerm, |
||||
func(ts tupleState) tupleState { |
||||
ts.ins = append(ts.ins, ts.oe) |
||||
ts.oe = nil |
||||
return ts |
||||
}, |
||||
), |
||||
) |
||||
|
||||
*tupleOpenEdgeTerm = *firstOf( |
||||
seq( |
||||
valueTerm, |
||||
valueTerm, |
||||
tupleOpenEdgeValueTailTerm, |
||||
func(val Value, ts tupleState) tupleState { |
||||
ts.oe = openEdgeIntoValue(val, ts.oe) |
||||
return ts |
||||
}, |
||||
), |
||||
seq( |
||||
tupleTerm, |
||||
tupleTerm, |
||||
tupleOpenEdgeTailTerm, |
||||
func(oe *OpenEdge, ts tupleState) tupleState { |
||||
ts.oe = oe |
||||
return ts |
||||
}, |
||||
), |
||||
) |
||||
|
||||
*tupleOpenEdgeTailTerm = *firstOf( |
||||
tupleEndTerm, |
||||
prefixed(trimmedRuneTerm(','), tupleTailTerm), |
||||
) |
||||
|
||||
*tupleOpenEdgeValueTailTerm = *firstOf( |
||||
tupleOpenEdgeTailTerm, |
||||
prefixed(trimmedRuneTerm('<'), tupleOpenEdgeTerm), |
||||
) |
||||
|
||||
*graphTerm = *seq( |
||||
stringerStr("graph"), |
||||
trimmedRuneTerm('{'), |
||||
graphTailTerm, |
||||
func(lr locatableRune, gs graphState) Value { |
||||
if gs.g == nil { |
||||
gs.g = new(Graph) |
||||
} |
||||
|
||||
return Value{Graph: gs.g, Location: lr.locate()} |
||||
}, |
||||
) |
||||
|
||||
*graphTailTerm = *firstOf( |
||||
graphEndTerm, |
||||
seq( |
||||
nameTerm, |
||||
nameTerm, |
||||
prefixed(trimmedRuneTerm('='), graphOpenEdgeTerm), |
||||
func(name Value, gs graphState) graphState { |
||||
if gs.g == nil { |
||||
gs.g = new(Graph) |
||||
} |
||||
|
||||
gs.g = gs.g.AddValueIn(name, gs.oe) |
||||
gs.oe = nil |
||||
return gs |
||||
}, |
||||
), |
||||
) |
||||
|
||||
*graphOpenEdgeTerm = *firstOf( |
||||
seq( |
||||
valueTerm, |
||||
valueTerm, |
||||
graphOpenEdgeValueTailTerm, |
||||
func(val Value, gs graphState) graphState { |
||||
gs.oe = openEdgeIntoValue(val, gs.oe) |
||||
return gs |
||||
}, |
||||
), |
||||
seq( |
||||
tupleTerm, |
||||
tupleTerm, |
||||
graphOpenEdgeTailTerm, |
||||
func(oe *OpenEdge, gs graphState) graphState { |
||||
gs.oe = oe |
||||
return gs |
||||
}, |
||||
), |
||||
) |
||||
|
||||
*graphOpenEdgeTailTerm = *firstOf( |
||||
graphEndTerm, |
||||
prefixed(trimmedRuneTerm(';'), graphTailTerm), |
||||
) |
||||
|
||||
*graphOpenEdgeValueTailTerm = *firstOf( |
||||
graphOpenEdgeTailTerm, |
||||
prefixed(trimmedRuneTerm('<'), graphOpenEdgeTerm), |
||||
) |
||||
|
||||
*valueTerm = *firstOf(nameTerm, numberTerm, graphTerm) |
||||
|
||||
return graphTerm, valueTerm |
||||
}() |
||||
|
||||
var topLevelTerm = trimmedTerm(valueTerm) |
||||
@ -0,0 +1,387 @@ |
||||
package gg |
||||
|
||||
import ( |
||||
"bytes" |
||||
"io" |
||||
"strconv" |
||||
"testing" |
||||
|
||||
"github.com/mediocregopher/ginger/graph" |
||||
"github.com/stretchr/testify/assert" |
||||
) |
||||
|
||||
func decoderLeftover(d *Decoder) string { |
||||
unread := make([]rune, len(d.unread)) |
||||
for i := range unread { |
||||
unread[i] = d.unread[i].r |
||||
} |
||||
|
||||
rest, err := io.ReadAll(d.br) |
||||
if err != nil { |
||||
panic(err) |
||||
} |
||||
return string(unread) + string(rest) |
||||
} |
||||
|
||||
func TestTermDecoding(t *testing.T) { |
||||
type test struct { |
||||
in string |
||||
exp Value |
||||
expErr string |
||||
leftover string |
||||
} |
||||
|
||||
runTests := func( |
||||
t *testing.T, name string, term *term[Value], tests []test, |
||||
) { |
||||
t.Run(name, func(t *testing.T) { |
||||
for i, test := range tests { |
||||
t.Run(strconv.Itoa(i), func(t *testing.T) { |
||||
dec := NewDecoder(bytes.NewBufferString(test.in)) |
||||
got, err := term.decodeFn(dec) |
||||
if test.expErr != "" { |
||||
assert.Error(t, err) |
||||
assert.Equal(t, test.expErr, err.Error()) |
||||
} else if assert.NoError(t, err) { |
||||
assert.True(t, |
||||
test.exp.Equal(got), |
||||
"\nexp:%v\ngot:%v", test.exp, got, |
||||
) |
||||
assert.Equal(t, test.leftover, decoderLeftover(dec)) |
||||
} |
||||
}) |
||||
} |
||||
}) |
||||
} |
||||
|
||||
expNum := func(row, col int, n int64) Value { |
||||
return Value{Number: &n, Location: Location{row, col}} |
||||
} |
||||
|
||||
runTests(t, "number", numberTerm, []test{ |
||||
{in: `0`, exp: expNum(1, 1, 0)}, |
||||
{in: `100`, exp: expNum(1, 1, 100)}, |
||||
{in: `-100`, exp: expNum(1, 1, -100)}, |
||||
{in: `0foo`, exp: expNum(1, 1, 0), leftover: "foo"}, |
||||
{in: `100foo`, exp: expNum(1, 1, 100), leftover: "foo"}, |
||||
}) |
||||
|
||||
expName := func(row, col int, name string) Value { |
||||
return Value{Name: &name, Location: Location{row, col}} |
||||
} |
||||
|
||||
expGraph := func(row, col int, g *Graph) Value { |
||||
return Value{Graph: g, Location: Location{row, col}} |
||||
} |
||||
|
||||
runTests(t, "name", nameTerm, []test{ |
||||
{in: `a`, exp: expName(1, 1, "a")}, |
||||
{in: `ab`, exp: expName(1, 1, "ab")}, |
||||
{in: `ab2c`, exp: expName(1, 1, "ab2c")}, |
||||
{in: `ab2c,`, exp: expName(1, 1, "ab2c"), leftover: ","}, |
||||
}) |
||||
|
||||
runTests(t, "graph", graphTerm, []test{ |
||||
{in: `{}`, exp: expGraph(1, 1, new(Graph))}, |
||||
{in: `{`, expErr: `1:2: expected '}' or name`}, |
||||
{in: `{a}`, expErr: `1:3: expected '='`}, |
||||
{in: `{a=}`, expErr: `1:4: expected name or number or graph or tuple`}, |
||||
{ |
||||
in: `{foo=a}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut(None, expName(6, 1, "a")), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{ foo = a }`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut(None, expName(6, 1, "a")), |
||||
), |
||||
), |
||||
}, |
||||
{in: `{1=a}`, expErr: `1:2: expected '}' or name`}, |
||||
{in: `{foo=a ,}`, expErr: `1:8: expected '}' or ';' or '<'`}, |
||||
{in: `{foo=a`, expErr: `1:7: expected '}' or ';' or '<'`}, |
||||
{ |
||||
in: `{foo=a<b}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expName(8, 1, "b"), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a< b <c}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.ValueOut( |
||||
Some(expName(8, 1, "b")), |
||||
expName(10, 1, "c"), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo =a<b<c<1 }`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.TupleOut( |
||||
Some(expName(8, 1, "b")), |
||||
graph.ValueOut( |
||||
Some(expName(10, 1, "c")), |
||||
expNum(12, 1, 1), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<b ; }`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expName(8, 1, "b"), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<b;bar=c}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expName(8, 1, "b"), |
||||
), |
||||
). |
||||
AddValueIn( |
||||
expName(10, 1, "bar"), |
||||
graph.ValueOut(None, expName(15, 1, "c")), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo= a<{ baz=1 } ; bar=c}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expGraph(8, 1, new(Graph).AddValueIn( |
||||
expName(9, 1, "baz"), |
||||
graph.ValueOut(None, expNum(13, 1, 1)), |
||||
)), |
||||
), |
||||
). |
||||
AddValueIn( |
||||
expName(16, 1, "bar"), |
||||
graph.ValueOut(None, expName(20, 1, "c")), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo= {baz=1} <a; bar=c}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expGraph(8, 1, new(Graph).AddValueIn( |
||||
expName(9, 1, "baz"), |
||||
graph.ValueOut(None, expNum(13, 1, 1)), |
||||
))), |
||||
expName(6, 1, "a"), |
||||
), |
||||
). |
||||
AddValueIn( |
||||
expName(16, 1, "bar"), |
||||
graph.ValueOut(None, expName(20, 1, "c")), |
||||
), |
||||
), |
||||
}, |
||||
}) |
||||
|
||||
runTests(t, "tuple", graphTerm, []test{ |
||||
{ |
||||
in: `{foo=(a)}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut(None, expName(6, 1, "a")), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=(a<b)}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expName(8, 1, "b"), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b)}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut( |
||||
Some(expName(6, 1, "a")), |
||||
expName(8, 1, "b"), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b,c)}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.ValueOut(None, expName(8, 1, "b")), |
||||
graph.ValueOut(None, expName(10, 1, "c")), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b<c)}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "b")), |
||||
graph.ValueOut(None, expName(8, 1, "c")), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b<(c))}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "b")), |
||||
graph.ValueOut(None, expName(8, 1, "c")), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b<(c,d<1))}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "b")), |
||||
graph.ValueOut(None, expName(8, 1, "c")), |
||||
graph.ValueOut( |
||||
Some(expName(12, 1, "d")), |
||||
expNum(10, 1, 1), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: `{foo=a<(b<( ( (c) ) ))}`, |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "a")), |
||||
graph.TupleOut( |
||||
Some(expName(6, 1, "b")), |
||||
graph.ValueOut(None, expName(8, 1, "c")), |
||||
), |
||||
), |
||||
), |
||||
), |
||||
}, |
||||
}) |
||||
|
||||
runTests(t, "comment", graphTerm, []test{ |
||||
{ |
||||
in: "*\n{}", |
||||
exp: expGraph(1, 1, new(Graph)), |
||||
}, |
||||
{ |
||||
in: "* ignore me!\n{}", |
||||
exp: expGraph(1, 1, new(Graph)), |
||||
}, |
||||
{ |
||||
in: "{* ignore me!\n}", |
||||
exp: expGraph(1, 1, new(Graph)), |
||||
}, |
||||
{ |
||||
in: "{foo* ignore me!\n = a}", |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut(None, expName(6, 1, "a")), |
||||
), |
||||
), |
||||
}, |
||||
{ |
||||
in: "{foo = a* ignore me!\n}", |
||||
exp: expGraph( |
||||
1, 1, new(Graph). |
||||
AddValueIn( |
||||
expName(2, 1, "foo"), |
||||
graph.ValueOut(None, expName(6, 1, "a")), |
||||
), |
||||
), |
||||
}, |
||||
}) |
||||
} |
||||
@ -1,23 +0,0 @@ |
||||
package gg |
||||
|
||||
import "io" |
||||
|
||||
type mockReader struct { |
||||
body []byte |
||||
err error |
||||
} |
||||
|
||||
func (r *mockReader) Read(b []byte) (int, error) { |
||||
|
||||
n := copy(b, r.body) |
||||
r.body = r.body[n:] |
||||
|
||||
if len(r.body) == 0 { |
||||
if r.err == nil { |
||||
return n, io.EOF |
||||
} |
||||
return n, r.err |
||||
} |
||||
|
||||
return n, nil |
||||
} |
||||
Loading…
Reference in new issue