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Behavior specs cleanup: Improve action specs

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redux
David Majda 10 years ago
parent b623396cb8
commit 3d9600b81b
1 changed files with 120 additions and 104 deletions
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224
spec/behavior/generated-parser-behavior.spec.js
Unescape Escape View File

@ -796,134 +796,150 @@ describe("generated parser behavior", function() {
});
describe("action", function() {
it("tranforms the expression result by returnung a value", function() {
var parser = PEG.buildParser('start = "a" { return 42; }', options);
expect(parser).toParse("a", 42);
});
describe("when the expression matches", function() {
it("returns the value returned by the code", function() {
var parser = PEG.buildParser('start = "a" { return 42; }', options);
it("is not called when the expression does not match", function() {
var parser = PEG.buildParser(
'start = "a" { throw "Boom!"; } / "b"',
options
);
expect(parser).toParse("a", 42);
});
expect(parser).toParse("b", "b");
});
describe("label variables", function() {
it("can access label variables from a labeled expression", function() {
var parser = PEG.buildParser('start = a:"a" { return a; }', options);
it("can use label variables", function() {
var parser = PEG.buildParser('start = a:"a" { return a; }', options);
expect(parser).toParse("a", "a");
});
expect(parser).toParse("a", "a");
});
it("can access label variables from a sequence with labeled elements", function() {
var parser = PEG.buildParser(
'start = a:"a" b:"b" c:"c" { return [a, b, c]; }',
options
);
it("can use the |text| function to get the text matched by the expression", function() {
var parser = PEG.buildParser(
'start = "a" "b" "c" { return text(); }',
options
);
expect(parser).toParse("abc", ["a", "b", "c"]);
});
});
expect(parser).toParse("abc", "abc");
});
describe("initializer variables & functions", function() {
it("can access variables defined in the initializer", function() {
var parser = PEG.buildParser([
'{ var v = 42 }',
'start = "a" { return v; }'
].join("\n"), options);
it("can use the |offset| function to get the current parse position", function() {
var parser = PEG.buildParser(
'start = "a" ("b" { return offset(); })',
options
);
expect(parser).toParse("a", 42);
});
expect(parser).toParse("ab", ["a", 1]);
});
it("can access functions defined in the initializer", function() {
var parser = PEG.buildParser([
'{ function f() { return 42; } }',
'start = "a" { return f(); }'
].join("\n"), options);
it("can use the |line| and |column| functions to get the current line and column", function() {
var parser = PEG.buildParser([
'{ var result; }',
'start = line (nl+ line)* { return result; }',
'line = thing (" "+ thing)*',
'thing = digit / mark',
'digit = [0-9]',
'mark = "x" { result = [line(), column()]; }',
'nl = ("\\r" / "\\n" / "\\u2028" / "\\u2029")'
].join("\n"), options);
expect(parser).toParse("a", 42);
});
});
expect(parser).toParse("1\n2\n\n3\n\n\n4 5 x", [7, 5]);
describe("available variables & functions", function() {
it("|parser| contains the parser object", function() {
var parser = PEG.buildParser(
'start = "a" { return parser; }',
options
);
/* Non-Unix newlines */
expect(parser).toParse("1\rx", [2, 1]); // Old Mac
expect(parser).toParse("1\r\nx", [2, 1]); // Windows
expect(parser).toParse("1\n\rx", [3, 1]); // mismatched
expect(parser).toParse("a", parser);
});
/* Strange newlines */
expect(parser).toParse("1\u2028x", [2, 1]); // line separator
expect(parser).toParse("1\u2029x", [2, 1]); // paragraph separator
});
it("|options| contains options", function() {
var parser = PEG.buildParser(
'start = "a" { return options; }',
options
);
it("can use variables defined in the initializer", function() {
var parser = PEG.buildParser([
'{ var v = 42 }',
'start = "a" { return v; }'
].join("\n"), options);
expect(parser).toParse("a", { a: 42 }, { a: 42 });
});
expect(parser).toParse("a", 42);
});
it("|text| returns text matched by the expression", function() {
var parser = PEG.buildParser(
'start = "a" { return text(); }',
options
);
it("can use the |expected| function to trigger an error", function() {
var parser = PEG.buildParser(
'start = "a" { expected("a"); }',
options
);
expect(parser).toParse("a", "a");
});
expect(parser).toFailToParse("a", {
message: 'Expected a but "a" found.',
expected: [{ type: "other", description: "a" }],
found: "a",
offset: 0,
line: 1,
column: 1
});
});
it("|offset|, |line|, and |column| return parse position, line, and column at the beginning of the expression", function() {
var parser = PEG.buildParser([
'{ var result; }',
'start = line (nl+ line)* { return result; }',
'line = thing (" "+ thing)*',
'thing = digit / mark',
'digit = [0-9]',
'mark = "x" { result = [offset(), line(), column()]; }',
'nl = [\\r\\n\\u2028\\u2029]'
].join("\n"), options);
expect(parser).toParse("1\n2\n\n3\n\n\n4 5 x", [13, 7, 5]);
/* Non-Unix newlines */
expect(parser).toParse("1\rx", [2, 2, 1]); // Old Mac
expect(parser).toParse("1\r\nx", [3, 2, 1]); // Windows
expect(parser).toParse("1\n\rx", [3, 3, 1]); // mismatched
/* Strange newlines */
expect(parser).toParse("1\u2028x", [2, 2, 1]); // line separator
expect(parser).toParse("1\u2029x", [2, 2, 1]); // paragraph separator
});
it("can use the |error| function to trigger an error", function() {
var parser = PEG.buildParser(
'start = "a" { error("a"); }',
options
);
it("|expected| terminates parsing and throws an exception", function() {
var parser = PEG.buildParser(
'start = "a" { expected("a"); }',
options
);
expect(parser).toFailToParse("a", {
message: 'Expected a but "a" found.',
expected: [{ type: "other", description: "a" }],
found: "a",
offset: 0,
line: 1,
column: 1
});
});
expect(parser).toFailToParse("a", {
message: "a",
expected: null,
found: "a",
offset: 0,
line: 1,
column: 1
it("|error| terminates parsing and throws an exception", function() {
var parser = PEG.buildParser(
'start = "a" { error("a"); }',
options
);
expect(parser).toFailToParse("a", {
message: "a",
expected: null,
found: "a",
offset: 0,
line: 1,
column: 1
});
});
});
});
it("can use functions defined in the initializer", function() {
var parser = PEG.buildParser([
'{ function f() { return 42; } }',
'start = "a" { return f(); }'
].join("\n"), options);
expect(parser).toParse("a", 42);
});
it("can use the |parser| variable to access the parser object", function() {
var parser = PEG.buildParser(
'start = "a" { return parser; }',
options
);
describe("when the expression doesn't match", function() {
it("reports match failure", function() {
var parser = PEG.buildParser('start = "a" { return 42; }', options);
expect(parser).toParse("a", parser);
});
expect(parser).toFailToParse("b");
});
it("can use options passed to the parser", function() {
var parser = PEG.buildParser(
'start = "a" { return options; }',
options
);
it("doesn't execute the code", function() {
var parser = PEG.buildParser(
'start = "a" { throw "Boom!"; } / "b"',
options
);
expect(parser).toParse("a", { a: 42 }, { a: 42 });
expect(parser).toParse("b");
});
});
});

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