aboutsummaryrefslogtreecommitdiff
path: root/tests/unit/spec/grammar/parser.go
diff options
context:
space:
mode:
Diffstat (limited to 'tests/unit/spec/grammar/parser.go')
-rw-r--r--tests/unit/spec/grammar/parser.go1439
1 files changed, 1439 insertions, 0 deletions
diff --git a/tests/unit/spec/grammar/parser.go b/tests/unit/spec/grammar/parser.go
new file mode 100644
index 0000000..773c466
--- /dev/null
+++ b/tests/unit/spec/grammar/parser.go
@@ -0,0 +1,1439 @@
+package parser
+
+import (
+ "strings"
+ "testing"
+
+ verr "urubu/error"
+)
+
+func TestLexer_Run(t *testing.T) {
+ idTok := func(text string) *token {
+ return newIDToken(text, newPosition(1, 0))
+ }
+
+ termPatTok := func(text string) *token {
+ return newTerminalPatternToken(text, newPosition(1, 0))
+ }
+
+ strTok := func(text string) *token {
+ return newStringLiteralToken(text, newPosition(1, 0))
+ }
+
+ symTok := func(kind tokenKind) *token {
+ return newSymbolToken(kind, newPosition(1, 0))
+ }
+
+ invalidTok := func(text string) *token {
+ return newInvalidToken(text, newPosition(1, 0))
+ }
+
+ tests := []struct {
+ caption string
+ src string
+ tokens []*token
+ err error
+ }{
+ {
+ caption: "the lexer can recognize all kinds of tokens",
+ src: `id"terminal"'string':|;@...#$()`,
+ tokens: []*token{
+ idTok("id"),
+ termPatTok("terminal"),
+ strTok(`string`),
+ symTok(tokenKindColon),
+ symTok(tokenKindOr),
+ symTok(tokenKindSemicolon),
+ symTok(tokenKindLabelMarker),
+ symTok(tokenKindExpantion),
+ symTok(tokenKindDirectiveMarker),
+ symTok(tokenKindOrderedSymbolMarker),
+ symTok(tokenKindLParen),
+ symTok(tokenKindRParen),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "the lexer can recognize keywords",
+ src: `fragment`,
+ tokens: []*token{
+ symTok(tokenKindKWFragment),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "the lexer can recognize character sequences and escape sequences in a terminal",
+ src: `"abc\"\\"`,
+ tokens: []*token{
+ termPatTok(`abc"\\`),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "backslashes are recognized as they are because escape sequences are not allowed in strings",
+ src: `'\\\'`,
+ tokens: []*token{
+ strTok(`\\\`),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "a pattern must include at least one character",
+ src: `""`,
+ err: synErrEmptyPattern,
+ },
+ {
+ caption: "a string must include at least one character",
+ src: `''`,
+ err: synErrEmptyString,
+ },
+ {
+ caption: "the lexer can recognize newlines and combine consecutive newlines into one",
+ src: "\u000A | \u000D | \u000D\u000A | \u000A\u000A \u000D\u000D \u000D\u000A\u000D\u000A",
+ tokens: []*token{
+ symTok(tokenKindNewline),
+ symTok(tokenKindOr),
+ symTok(tokenKindNewline),
+ symTok(tokenKindOr),
+ symTok(tokenKindNewline),
+ symTok(tokenKindOr),
+ symTok(tokenKindNewline),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "the lexer ignores line comments",
+ src: `
+// This is the first comment.
+foo
+// This is the second comment.
+// This is the third comment.
+bar // This is the fourth comment.
+`,
+ tokens: []*token{
+ symTok(tokenKindNewline),
+ idTok("foo"),
+ symTok(tokenKindNewline),
+ idTok("bar"),
+ symTok(tokenKindNewline),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "an identifier cannot contain the capital-case letters",
+ src: `Abc`,
+ err: synErrIDInvalidChar,
+ },
+ {
+ caption: "an identifier cannot contain the capital-case letters",
+ src: `Zyx`,
+ err: synErrIDInvalidChar,
+ },
+ {
+ caption: "the underscore cannot be placed at the beginning of an identifier",
+ src: `_abc`,
+ err: synErrIDInvalidUnderscorePos,
+ },
+ {
+ caption: "the underscore cannot be placed at the end of an identifier",
+ src: `abc_`,
+ err: synErrIDInvalidUnderscorePos,
+ },
+ {
+ caption: "the underscore cannot be placed consecutively",
+ src: `a__b`,
+ err: synErrIDConsecutiveUnderscores,
+ },
+ {
+ caption: "the digits cannot be placed at the biginning of an identifier",
+ src: `0abc`,
+ err: synErrIDInvalidDigitsPos,
+ },
+ {
+ caption: "the digits cannot be placed at the biginning of an identifier",
+ src: `9abc`,
+ err: synErrIDInvalidDigitsPos,
+ },
+ {
+ caption: "an unclosed terminal is not a valid token",
+ src: `"abc`,
+ err: synErrUnclosedTerminal,
+ },
+ {
+ caption: "an incompleted escape sequence in a pattern is not a valid token",
+ src: `"\`,
+ err: synErrIncompletedEscSeq,
+ },
+ {
+ caption: "an unclosed string is not a valid token",
+ src: `'abc`,
+ err: synErrUnclosedString,
+ },
+ {
+ caption: "the lexer can recognize valid tokens following an invalid token",
+ src: `abc!!!def`,
+ tokens: []*token{
+ idTok("abc"),
+ invalidTok("!!!"),
+ idTok("def"),
+ newEOFToken(),
+ },
+ },
+ {
+ caption: "the lexer skips white spaces",
+ // \u0009: HT
+ // \u0020: SP
+ src: "a\u0009b\u0020c",
+ tokens: []*token{
+ idTok("a"),
+ idTok("b"),
+ idTok("c"),
+ newEOFToken(),
+ },
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.caption, func(t *testing.T) {
+ l, err := newLexer(strings.NewReader(tt.src))
+ if err != nil {
+ t.Fatal(err)
+ }
+ n := 0
+ for {
+ var tok *token
+ tok, err = l.next()
+ if err != nil {
+ break
+ }
+ testToken(t, tok, tt.tokens[n])
+ n++
+ if tok.kind == tokenKindEOF {
+ break
+ }
+ }
+ if tt.err != nil {
+ synErr, ok := err.(*verr.SpecError)
+ if !ok {
+ t.Fatalf("unexpected error; want: %v, got: %v", tt.err, err)
+ }
+ if tt.err != synErr.Cause {
+ t.Fatalf("unexpected error; want: %v, got: %v", tt.err, synErr.Cause)
+ }
+ } else {
+ if err != nil {
+ t.Fatalf("unexpected error; want: %v, got: %v", tt.err, err)
+ }
+ }
+ })
+ }
+}
+
+func testToken(t *testing.T, tok, expected *token) {
+ t.Helper()
+ if tok.kind != expected.kind || tok.text != expected.text {
+ t.Fatalf("unexpected token; want: %+v, got: %+v", expected, tok)
+ }
+}
+
+func TestParse(t *testing.T) {
+ name := func(param *ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: "name",
+ Parameters: []*ParameterNode{param},
+ }
+ }
+ prec := func(param *ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: "prec",
+ Parameters: []*ParameterNode{param},
+ }
+ }
+ leftAssoc := func(params ...*ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: "left",
+ Parameters: params,
+ }
+ }
+ rightAssoc := func(params ...*ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: "right",
+ Parameters: params,
+ }
+ }
+ assign := func(params ...*ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: "assign",
+ Parameters: params,
+ }
+ }
+ prod := func(lhs string, alts ...*AlternativeNode) *ProductionNode {
+ return &ProductionNode{
+ LHS: lhs,
+ RHS: alts,
+ }
+ }
+ withProdPos := func(prod *ProductionNode, pos Position) *ProductionNode {
+ prod.Pos = pos
+ return prod
+ }
+ withProdDir := func(prod *ProductionNode, dirs ...*DirectiveNode) *ProductionNode {
+ prod.Directives = dirs
+ return prod
+ }
+ alt := func(elems ...*ElementNode) *AlternativeNode {
+ return &AlternativeNode{
+ Elements: elems,
+ }
+ }
+ withAltPos := func(alt *AlternativeNode, pos Position) *AlternativeNode {
+ alt.Pos = pos
+ return alt
+ }
+ withAltDir := func(alt *AlternativeNode, dirs ...*DirectiveNode) *AlternativeNode {
+ alt.Directives = dirs
+ return alt
+ }
+ dir := func(name string, params ...*ParameterNode) *DirectiveNode {
+ return &DirectiveNode{
+ Name: name,
+ Parameters: params,
+ }
+ }
+ withDirPos := func(dir *DirectiveNode, pos Position) *DirectiveNode {
+ dir.Pos = pos
+ return dir
+ }
+ idParam := func(id string) *ParameterNode {
+ return &ParameterNode{
+ ID: id,
+ }
+ }
+ ordSymParam := func(id string) *ParameterNode {
+ return &ParameterNode{
+ OrderedSymbol: id,
+ }
+ }
+ exp := func(param *ParameterNode) *ParameterNode {
+ param.Expansion = true
+ return param
+ }
+ group := func(dirs ...*DirectiveNode) *ParameterNode {
+ return &ParameterNode{
+ Group: dirs,
+ }
+ }
+ withParamPos := func(param *ParameterNode, pos Position) *ParameterNode {
+ param.Pos = pos
+ return param
+ }
+ id := func(id string) *ElementNode {
+ return &ElementNode{
+ ID: id,
+ }
+ }
+ pat := func(p string) *ElementNode {
+ return &ElementNode{
+ Pattern: p,
+ }
+ }
+ label := func(name string) *LabelNode {
+ return &LabelNode{
+ Name: name,
+ }
+ }
+ withLabelPos := func(label *LabelNode, pos Position) *LabelNode {
+ label.Pos = pos
+ return label
+ }
+ withLabel := func(elem *ElementNode, label *LabelNode) *ElementNode {
+ elem.Label = label
+ return elem
+ }
+ withElemPos := func(elem *ElementNode, pos Position) *ElementNode {
+ elem.Pos = pos
+ return elem
+ }
+ frag := func(lhs string, rhs string) *FragmentNode {
+ return &FragmentNode{
+ LHS: lhs,
+ RHS: rhs,
+ }
+ }
+ withFragmentPos := func(frag *FragmentNode, pos Position) *FragmentNode {
+ frag.Pos = pos
+ return frag
+ }
+ newPos := func(row int) Position {
+ return Position{
+ Row: row,
+ Col: 0,
+ }
+ }
+
+ tests := []struct {
+ caption string
+ src string
+ checkPosition bool
+ ast *RootNode
+ synErr *SyntaxError
+ }{
+ {
+ caption: "a grammar can contain top-level directives",
+ src: `
+#name test;
+
+#prec (
+ #left a b $x1
+ #right c d $x2
+ #assign e f $x3
+);
+`,
+ ast: &RootNode{
+ Directives: []*DirectiveNode{
+ withDirPos(
+ name(
+ withParamPos(
+ idParam("test"),
+ newPos(2),
+ ),
+ ),
+ newPos(2),
+ ),
+ withDirPos(
+ prec(
+ withParamPos(
+ group(
+ withDirPos(
+ leftAssoc(
+ withParamPos(
+ idParam("a"),
+ newPos(5),
+ ),
+ withParamPos(
+ idParam("b"),
+ newPos(5),
+ ),
+ withParamPos(
+ ordSymParam("x1"),
+ newPos(5),
+ ),
+ ),
+ newPos(5),
+ ),
+ withDirPos(
+ rightAssoc(
+ withParamPos(
+ idParam("c"),
+ newPos(6),
+ ),
+ withParamPos(
+ idParam("d"),
+ newPos(6),
+ ),
+ withParamPos(
+ ordSymParam("x2"),
+ newPos(6),
+ ),
+ ),
+ newPos(6),
+ ),
+ withDirPos(
+ assign(
+ withParamPos(
+ idParam("e"),
+ newPos(7),
+ ),
+ withParamPos(
+ idParam("f"),
+ newPos(7),
+ ),
+ withParamPos(
+ ordSymParam("x3"),
+ newPos(7),
+ ),
+ ),
+ newPos(7),
+ ),
+ ),
+ newPos(4),
+ ),
+ ),
+ newPos(4),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a top-level directive must be followed by ';'",
+ src: `
+#name test
+`,
+ synErr: synErrTopLevelDirNoSemicolon,
+ },
+ {
+ caption: "a directive group must be closed by ')'",
+ src: `
+#prec (
+ #left a b
+;
+`,
+ synErr: synErrUnclosedDirGroup,
+ },
+ {
+ caption: "an ordered symbol marker '$' must be followed by and ID",
+ src: `
+#prec (
+ #assign $
+);
+`,
+ synErr: synErrNoOrderedSymbolName,
+ },
+ {
+ caption: "single production is a valid grammar",
+ src: `a: "a";`,
+ ast: &RootNode{
+ LexProductions: []*ProductionNode{
+ prod("a", alt(pat("a"))),
+ },
+ },
+ },
+ {
+ caption: "multiple productions are a valid grammar",
+ src: `
+e
+ : e add t
+ | e sub t
+ | t
+ ;
+t
+ : t mul f
+ | t div f
+ | f
+ ;
+f
+ : l_paren e r_paren
+ | id
+ ;
+
+add
+ : '+';
+sub
+ : '-';
+mul
+ : '*';
+div
+ : '/';
+l_paren
+ : '(';
+r_paren
+ : ')';
+id
+ : "[A-Za-z_][0-9A-Za-z_]*";
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("e",
+ alt(id("e"), id("add"), id("t")),
+ alt(id("e"), id("sub"), id("t")),
+ alt(id("t")),
+ ),
+ prod("t",
+ alt(id("t"), id("mul"), id("f")),
+ alt(id("t"), id("div"), id("f")),
+ alt(id("f")),
+ ),
+ prod("f",
+ alt(id("l_paren"), id("e"), id("r_paren")),
+ alt(id("id")),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ prod("add", alt(pat(`+`))),
+ prod("sub", alt(pat(`-`))),
+ prod("mul", alt(pat(`*`))),
+ prod("div", alt(pat(`/`))),
+ prod("l_paren", alt(pat(`(`))),
+ prod("r_paren", alt(pat(`)`))),
+ prod("id", alt(pat(`[A-Za-z_][0-9A-Za-z_]*`))),
+ },
+ },
+ },
+ {
+ caption: "productions can contain the empty alternative",
+ src: `
+a
+ : foo
+ |
+ ;
+b
+ :
+ | bar
+ ;
+c
+ :
+ ;
+
+foo
+ : 'foo';
+bar
+ : 'bar';
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("a",
+ alt(id("foo")),
+ alt(),
+ ),
+ prod("b",
+ alt(),
+ alt(id("bar")),
+ ),
+ prod("c",
+ alt(),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ prod("foo", alt(pat(`foo`))),
+ prod("bar", alt(pat(`bar`))),
+ },
+ },
+ },
+ {
+ caption: "a production cannot contain an ordered symbol",
+ src: `
+a: $x;
+`,
+ synErr: synErrNoSemicolon,
+ },
+ {
+ caption: "an alternative cannot contain a pattern directly",
+ src: `
+s
+ : "foo" bar
+ ;
+
+bar
+ : "bar";
+`,
+ synErr: synErrPatternInAlt,
+ },
+ {
+ caption: "an alternative cannot contain a string directly",
+ src: `
+s
+ : 'foo' bar
+ ;
+bar
+ : "bar";
+`,
+ synErr: synErrPatternInAlt,
+ },
+ {
+ caption: "a terminal symbol can be defined using a string literal",
+ src: `
+foo
+ : 'foo';
+`,
+ ast: &RootNode{
+ LexProductions: []*ProductionNode{
+ prod("foo",
+ alt(pat(`foo`)),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a terminal symbol can be defined using a pattern",
+ src: `
+foo
+ : "foo";
+`,
+ ast: &RootNode{
+ LexProductions: []*ProductionNode{
+ prod("foo",
+ alt(pat(`foo`)),
+ ),
+ },
+ },
+ },
+ {
+ caption: "`fragment` is a reserved word",
+ src: `fragment: 'fragment';`,
+ synErr: synErrNoProductionName,
+ },
+ {
+ caption: "when a source contains an unknown token, the parser raises a syntax error",
+ src: `a: !;`,
+ synErr: synErrInvalidToken,
+ },
+ {
+ caption: "a production must have its name as the first element",
+ src: `: "a";`,
+ synErr: synErrNoProductionName,
+ },
+ {
+ caption: "':' must precede an alternative",
+ src: `a "a";`,
+ synErr: synErrNoColon,
+ },
+ {
+ caption: "';' must follow a production",
+ src: `a: "a"`,
+ synErr: synErrNoSemicolon,
+ },
+ {
+ caption: "';' can only appear at the end of a production",
+ src: `;`,
+ synErr: synErrNoProductionName,
+ },
+ {
+ caption: "a grammar can contain fragments",
+ src: `
+s
+ : tagline
+ ;
+tagline: "\f{words} IS OUT THERE.";
+fragment words: "[A-Za-z\u{0020}]+";
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("s",
+ alt(id("tagline")),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ prod("tagline",
+ alt(pat(`\f{words} IS OUT THERE.`)),
+ ),
+ },
+ Fragments: []*FragmentNode{
+ frag("words", `[A-Za-z\u{0020}]+`),
+ },
+ },
+ },
+ {
+ caption: "the lexer treats consecutive lines as a single token but can count lines correctly",
+ src: `// This line precedes line comments and blank lines.
+// This is a line comment.
+
+
+s
+ : foo
+ ;
+
+
+// This line is sandwiched between blank lines.
+
+
+foo: 'foo';
+`,
+ checkPosition: true,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ withProdPos(
+ prod("s",
+ withAltPos(
+ alt(
+ withElemPos(
+ id("foo"),
+ newPos(6),
+ ),
+ ),
+ newPos(6),
+ ),
+ ),
+ newPos(5),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ withProdPos(
+ prod("foo",
+ withAltPos(
+ alt(
+ withElemPos(
+ pat(`foo`),
+ newPos(13),
+ ),
+ ),
+ newPos(13),
+ ),
+ ),
+ newPos(13),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a grammar can contain production directives and alternative directives",
+ src: `
+mode_tran_seq
+ : mode_tran_seq mode_tran
+ | mode_tran
+ ;
+mode_tran
+ : push_m1
+ | push_m2
+ | pop_m1
+ | pop_m2
+ ;
+
+push_m1 #push m1
+ : "->";
+push_m2 #mode m1 #push m2
+ : "-->";
+pop_m1 #mode m1 #pop
+ : "<-";
+pop_m2 #mode m2 #pop
+ : "<--";
+whitespace #mode default m1 m2 #skip
+ : "\u{0020}+";
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("mode_tran_seq",
+ alt(id("mode_tran_seq"), id("mode_tran")),
+ alt(id("mode_tran")),
+ ),
+ prod("mode_tran",
+ alt(id("push_m1")),
+ alt(id("push_m2")),
+ alt(id("pop_m1")),
+ alt(id("pop_m2")),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ withProdDir(
+ prod("push_m1",
+ alt(pat(`->`)),
+ ),
+ dir("push", idParam("m1")),
+ ),
+ withProdDir(
+ prod("push_m2",
+ alt(pat(`-->`)),
+ ),
+ dir("mode", idParam("m1")),
+ dir("push", idParam("m2")),
+ ),
+ withProdDir(
+ prod("pop_m1",
+ alt(pat(`<-`)),
+ ),
+ dir("mode", idParam("m1")),
+ dir("pop"),
+ ),
+ withProdDir(
+ prod("pop_m2",
+ alt(pat(`<--`)),
+ ),
+ dir("mode", idParam("m2")),
+ dir("pop"),
+ ),
+ withProdDir(
+ prod("whitespace",
+ alt(pat(`\u{0020}+`)),
+ ),
+ dir("mode", idParam("default"), idParam("m1"), idParam("m2")),
+ dir("skip"),
+ ),
+ },
+ },
+ },
+ {
+ caption: "an alternative of a production can have multiple alternative directives",
+ src: `
+s
+ : foo bar #prec baz #ast foo bar
+ ;
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("s",
+ withAltDir(
+ alt(id("foo"), id("bar")),
+ dir("prec", idParam("baz")),
+ dir("ast", idParam("foo"), idParam("bar")),
+ ),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a lexical production can have multiple production directives",
+ src: `
+foo #mode a #push b
+ : 'foo';
+`,
+ ast: &RootNode{
+ LexProductions: []*ProductionNode{
+ withProdDir(
+ prod("foo",
+ alt(pat("foo")),
+ ),
+ dir("mode", idParam("a")),
+ dir("push", idParam("b")),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a production must be followed by a newline",
+ src: `
+s: foo; foo: "foo";
+`,
+ synErr: synErrSemicolonNoNewline,
+ },
+ {
+ caption: "a grammar can contain 'ast' directives and expansion operator",
+ src: `
+s
+ : foo bar_list #ast foo bar_list
+ ;
+bar_list
+ : bar_list bar #ast bar_list... bar
+ | bar #ast bar
+ ;
+foo: "foo";
+bar: "bar";
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ prod("s",
+ withAltDir(
+ alt(id("foo"), id("bar_list")),
+ dir("ast", idParam("foo"), idParam("bar_list")),
+ ),
+ ),
+ prod("bar_list",
+ withAltDir(
+ alt(id("bar_list"), id("bar")),
+ dir("ast", exp(idParam("bar_list")), idParam("bar")),
+ ),
+ withAltDir(
+ alt(id("bar")),
+ dir("ast", idParam("bar")),
+ ),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ prod("foo",
+ alt(pat("foo")),
+ ),
+ prod("bar",
+ alt(pat("bar")),
+ ),
+ },
+ },
+ },
+ {
+ caption: "an expansion operator must be preceded by an identifier",
+ src: `
+s
+ : foo #ast ...
+ ;
+`,
+ synErr: synErrStrayExpOp,
+ },
+ {
+ caption: "an expansion operator must be preceded by an identifier",
+ src: `
+a
+ : foo #ast ... foo
+ ;
+`,
+ synErr: synErrStrayExpOp,
+ },
+ {
+ caption: "an expansion operator cannot be applied to a pattern",
+ src: `
+a
+ : "foo" #ast "foo"...
+ ;
+`,
+ synErr: synErrInvalidExpOperand,
+ },
+ {
+ caption: "an expansion operator cannot be applied to a string",
+ src: `
+a
+ : 'foo' #ast 'foo'...
+ ;
+`,
+ synErr: synErrInvalidExpOperand,
+ },
+ {
+ caption: "an expansion operator cannot be applied to an ordered symbol",
+ src: `
+a
+ : foo #ast $foo...
+ ;
+`,
+ synErr: synErrInvalidExpOperand,
+ },
+ {
+ caption: "an expansion operator cannot be applied to a directive group",
+ src: `
+a
+ : foo #ast ()...
+ ;
+`,
+ synErr: synErrInvalidExpOperand,
+ },
+ {
+ caption: "an AST has node positions",
+ src: `
+exp
+ : exp add id #ast exp id
+ | id
+ ;
+
+whitespace #skip
+ : "\u{0020}+";
+add
+ : '+';
+id
+ : "\f{letter}(\f{letter}|\f{number})*";
+fragment letter
+ : "[A-Za-z_]";
+fragment number
+ : "[0-9]";
+`,
+ checkPosition: true,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ withProdPos(
+ prod("exp",
+ withAltPos(
+ withAltDir(
+ alt(
+ withElemPos(id("exp"), newPos(3)),
+ withElemPos(id("add"), newPos(3)),
+ withElemPos(id("id"), newPos(3)),
+ ),
+ withDirPos(
+ dir("ast",
+ withParamPos(idParam("exp"), newPos(3)),
+ withParamPos(idParam("id"), newPos(3)),
+ ),
+ newPos(3),
+ ),
+ ),
+ newPos(3),
+ ),
+ withAltPos(
+ alt(
+ withElemPos(id("id"), newPos(4)),
+ ),
+ newPos(4),
+ ),
+ ),
+ newPos(2),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ withProdPos(
+ withProdDir(
+ prod("whitespace",
+ withAltPos(
+ alt(
+ withElemPos(
+ pat(`\u{0020}+`),
+ newPos(8),
+ ),
+ ),
+ newPos(8),
+ ),
+ ),
+ withDirPos(
+ dir("skip"),
+ newPos(7),
+ ),
+ ),
+ newPos(7),
+ ),
+ withProdPos(
+ prod("add",
+ withAltPos(
+ alt(
+ withElemPos(
+ pat(`+`),
+ newPos(10),
+ ),
+ ),
+ newPos(10),
+ ),
+ ),
+ newPos(9),
+ ),
+ withProdPos(
+ prod("id",
+ withAltPos(
+ alt(
+ withElemPos(
+ pat(`\f{letter}(\f{letter}|\f{number})*`),
+ newPos(12),
+ ),
+ ),
+ newPos(12),
+ ),
+ ),
+ newPos(11),
+ ),
+ },
+ Fragments: []*FragmentNode{
+ withFragmentPos(
+ frag("letter", "[A-Za-z_]"),
+ newPos(13),
+ ),
+ withFragmentPos(
+ frag("number", "[0-9]"),
+ newPos(15),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a symbol can have a label",
+ src: `
+expr
+ : term@lhs add term@rhs
+ ;
+`,
+ ast: &RootNode{
+ Productions: []*ProductionNode{
+ withProdPos(
+ prod("expr",
+ withAltPos(
+ alt(
+ withElemPos(
+ withLabel(
+ id("term"),
+ withLabelPos(
+ label("lhs"),
+ newPos(3),
+ ),
+ ),
+ newPos(3),
+ ),
+ withElemPos(
+ id("add"),
+ newPos(3),
+ ),
+ withElemPos(
+ withLabel(
+ id("term"),
+ withLabelPos(
+ label("rhs"),
+ newPos(3),
+ ),
+ ),
+ newPos(3),
+ ),
+ ),
+ newPos(3),
+ ),
+ ),
+ newPos(2),
+ ),
+ },
+ },
+ },
+ {
+ caption: "a label must be an identifier, not a string",
+ src: `
+foo
+ : bar@'baz'
+ ;
+`,
+ synErr: synErrNoLabel,
+ },
+ {
+ caption: "a label must be an identifier, not a pattern",
+ src: `
+foo
+ : bar@"baz"
+ ;
+`,
+ synErr: synErrNoLabel,
+ },
+ {
+ caption: "the symbol marker @ must be followed by an identifier",
+ src: `
+foo
+ : bar@
+ ;
+`,
+ synErr: synErrNoLabel,
+ },
+ {
+ caption: "a symbol cannot have more than or equal to two labels",
+ src: `
+foo
+ : bar@baz@bra
+ ;
+`,
+ synErr: synErrLabelWithNoSymbol,
+ },
+ {
+ caption: "a label must follow a symbol",
+ src: `
+foo
+ : @baz
+ ;
+`,
+ synErr: synErrLabelWithNoSymbol,
+ },
+ {
+ caption: "a grammar can contain left and right associativities",
+ src: `
+#prec (
+ #left l1 l2
+ #left l3
+ #right r1 r2
+ #right r3
+);
+
+s
+ : id l1 id l2 id l3 id
+ | id r1 id r2 id r3 id
+ ;
+
+whitespaces #skip
+ : "[\u{0009}\u{0020}]+";
+l1
+ : 'l1';
+l2
+ : 'l2';
+l3
+ : 'l3';
+r1
+ : 'r1';
+r2
+ : 'r2';
+r3
+ : 'r3';
+id
+ : "[A-Za-z0-9_]+";
+`,
+ ast: &RootNode{
+ Directives: []*DirectiveNode{
+ withDirPos(
+ prec(
+ withParamPos(
+ group(
+ withDirPos(
+ leftAssoc(
+ withParamPos(idParam("l1"), newPos(3)),
+ withParamPos(idParam("l2"), newPos(3)),
+ ),
+ newPos(3),
+ ),
+ withDirPos(
+ leftAssoc(
+ withParamPos(idParam("l3"), newPos(4)),
+ ),
+ newPos(4),
+ ),
+ withDirPos(
+ rightAssoc(
+ withParamPos(idParam("r1"), newPos(5)),
+ withParamPos(idParam("r2"), newPos(5)),
+ ),
+ newPos(5),
+ ),
+ withDirPos(
+ rightAssoc(
+ withParamPos(idParam("r3"), newPos(6)),
+ ),
+ newPos(6),
+ ),
+ ),
+ newPos(2),
+ ),
+ ),
+ newPos(2),
+ ),
+ },
+ Productions: []*ProductionNode{
+ prod("s",
+ alt(id(`id`), id(`l1`), id(`id`), id(`l2`), id(`id`), id(`l3`), id(`id`)),
+ alt(id(`id`), id(`r1`), id(`id`), id(`r2`), id(`id`), id(`r3`), id(`id`)),
+ ),
+ },
+ LexProductions: []*ProductionNode{
+ withProdDir(
+ prod("whitespaces",
+ alt(pat(`[\u{0009}\u{0020}]+`)),
+ ),
+ dir("skip"),
+ ),
+ prod("l1", alt(pat(`l1`))),
+ prod("l2", alt(pat(`l2`))),
+ prod("l3", alt(pat(`l3`))),
+ prod("r1", alt(pat(`r1`))),
+ prod("r2", alt(pat(`r2`))),
+ prod("r3", alt(pat(`r3`))),
+ prod("id", alt(pat(`[A-Za-z0-9_]+`))),
+ },
+ },
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.caption, func(t *testing.T) {
+ ast, err := Parse(strings.NewReader(tt.src))
+ if tt.synErr != nil {
+ synErrs, ok := err.(verr.SpecErrors)
+ if !ok {
+ t.Fatalf("unexpected error; want: %v, got: %v", tt.synErr, err)
+ }
+ synErr := synErrs[0]
+ if tt.synErr != synErr.Cause {
+ t.Fatalf("unexpected error; want: %v, got: %v", tt.synErr, synErr.Cause)
+ }
+ if ast != nil {
+ t.Fatalf("AST must be nil")
+ }
+ } else {
+ if err != nil {
+ t.Fatalf("unexpected error: %v", err)
+ }
+ if ast == nil {
+ t.Fatalf("AST must be non-nil")
+ }
+ testRootNode(t, ast, tt.ast, tt.checkPosition)
+ }
+ })
+ }
+}
+
+func testRootNode(t *testing.T, root, expected *RootNode, checkPosition bool) {
+ t.Helper()
+ if len(root.Productions) != len(expected.Productions) {
+ t.Fatalf("unexpected length of productions; want: %v, got: %v", len(expected.Productions), len(root.Productions))
+ }
+ if len(root.Directives) != len(expected.Directives) {
+ t.Fatalf("unexpected length of top-level directives; want: %v, got: %v", len(expected.Directives), len(root.Directives))
+ }
+ for i, dir := range root.Directives {
+ testDirectives(t, []*DirectiveNode{dir}, []*DirectiveNode{expected.Directives[i]}, true)
+ }
+ for i, prod := range root.Productions {
+ testProductionNode(t, prod, expected.Productions[i], checkPosition)
+ }
+ for i, prod := range root.LexProductions {
+ testProductionNode(t, prod, expected.LexProductions[i], checkPosition)
+ }
+ for i, frag := range root.Fragments {
+ testFragmentNode(t, frag, expected.Fragments[i], checkPosition)
+ }
+}
+
+func testProductionNode(t *testing.T, prod, expected *ProductionNode, checkPosition bool) {
+ t.Helper()
+ if len(expected.Directives) != len(prod.Directives) {
+ t.Fatalf("unexpected directive count; want: %v directives, got: %v directives", len(expected.Directives), len(prod.Directives))
+ }
+ if len(expected.Directives) > 0 {
+ testDirectives(t, prod.Directives, expected.Directives, checkPosition)
+ }
+ if prod.LHS != expected.LHS {
+ t.Fatalf("unexpected LHS; want: %v, got: %v", expected.LHS, prod.LHS)
+ }
+ if len(prod.RHS) != len(expected.RHS) {
+ t.Fatalf("unexpected length of an RHS; want: %v, got: %v", len(expected.RHS), len(prod.RHS))
+ }
+ for i, alt := range prod.RHS {
+ testAlternativeNode(t, alt, expected.RHS[i], checkPosition)
+ }
+ if checkPosition {
+ testPosition(t, prod.Pos, expected.Pos)
+ }
+}
+
+func testFragmentNode(t *testing.T, frag, expected *FragmentNode, checkPosition bool) {
+ t.Helper()
+ if frag.LHS != expected.LHS {
+ t.Fatalf("unexpected LHS; want: %v, got: %v", expected.LHS, frag.LHS)
+ }
+ if frag.RHS != expected.RHS {
+ t.Fatalf("unexpected RHS; want: %v, got: %v", expected.RHS, frag.RHS)
+ }
+ if checkPosition {
+ testPosition(t, frag.Pos, expected.Pos)
+ }
+}
+
+func testAlternativeNode(t *testing.T, alt, expected *AlternativeNode, checkPosition bool) {
+ t.Helper()
+ if len(alt.Elements) != len(expected.Elements) {
+ t.Fatalf("unexpected length of elements; want: %v, got: %v", len(expected.Elements), len(alt.Elements))
+ }
+ for i, elem := range alt.Elements {
+ testElementNode(t, elem, expected.Elements[i], checkPosition)
+ }
+ if len(alt.Directives) != len(expected.Directives) {
+ t.Fatalf("unexpected alternative directive count; want: %v directive, got: %v directive", len(expected.Directives), len(alt.Directives))
+ }
+ if len(alt.Directives) > 0 {
+ testDirectives(t, alt.Directives, expected.Directives, checkPosition)
+ }
+ if checkPosition {
+ testPosition(t, alt.Pos, expected.Pos)
+ }
+}
+
+func testElementNode(t *testing.T, elem, expected *ElementNode, checkPosition bool) {
+ t.Helper()
+ if elem.ID != expected.ID {
+ t.Fatalf("unexpected ID; want: %v, got: %v", expected.ID, elem.ID)
+ }
+ if elem.Pattern != expected.Pattern {
+ t.Fatalf("unexpected pattern; want: %v, got: %v", expected.Pattern, elem.Pattern)
+ }
+ if checkPosition {
+ testPosition(t, elem.Pos, expected.Pos)
+ }
+}
+
+func testDirectives(t *testing.T, dirs, expected []*DirectiveNode, checkPosition bool) {
+ t.Helper()
+ for i, exp := range expected {
+ dir := dirs[i]
+
+ if exp.Name != dir.Name {
+ t.Fatalf("unexpected directive name; want: %+v, got: %+v", exp.Name, dir.Name)
+ }
+ if len(exp.Parameters) != len(dir.Parameters) {
+ t.Fatalf("unexpected directive parameter; want: %+v, got: %+v", exp.Parameters, dir.Parameters)
+ }
+ for j, expParam := range exp.Parameters {
+ testParameter(t, dir.Parameters[j], expParam, checkPosition)
+ }
+ if checkPosition {
+ testPosition(t, dir.Pos, exp.Pos)
+ }
+ }
+}
+
+func testParameter(t *testing.T, param, expected *ParameterNode, checkPosition bool) {
+ t.Helper()
+ if param.ID != expected.ID {
+ t.Fatalf("unexpected ID parameter; want: %v, got: %v", expected.ID, param.ID)
+ }
+ if param.String != expected.String {
+ t.Fatalf("unexpected string parameter; want: %v, got: %v", expected.ID, param.ID)
+ }
+ if param.Expansion != expected.Expansion {
+ t.Fatalf("unexpected expansion; want: %v, got: %v", expected.Expansion, param.Expansion)
+ }
+ if checkPosition {
+ testPosition(t, param.Pos, expected.Pos)
+ }
+}
+
+func testPosition(t *testing.T, pos, expected Position) {
+ t.Helper()
+ if pos.Row != expected.Row {
+ t.Fatalf("unexpected position want: %+v, got: %+v", expected, pos)
+ }
+}
generated by cgit v1.2.3 (git 2.49.0) at 2025-07-13 10:48:54 +0000