PureYAML/Tests/ParsingErrorTests.swift
Mihaela Mihaljevic a8950e118c Merge conformance/yaml-test-suite-gaps: the libyaml port becomes the engine on main
The ported engine wins every conflict: main's post-fork patches to the
hand-rolled Scanner and TokenEventParser land on deleted files and are
dropped; their behaviors are carried by the port and guarded by the
whole-suite conformance gate (402/402 passing).

Merge adaptations, all gates green (style, namespacing, forbidden
patterns, changelog, roadmap, swiftformat, swiftlint strict, build,
full test suite, whole-suite conformance sweep):

- PureYAMLJSON representability rules move onto the Check algebra,
  replacing the retired legacy Rule type.
- The permissive tag-handle pre-pass is removed; the port rejects an
  undefined handle at parse time (suite case QLJ7) and the validation
  report carries it as a parse diagnostic.
- EventStreamComposer's nested types split one-per-file per the
  namespacing gate.
- Tests pinned to old-engine behavior were re-verified against the
  reference and updated: libyaml rejects an explicit-key continuation
  ending at a value colon, and suite case QB6E requires rejecting a
  quoted continuation at column 0.
- CHANGELOG unreleased entries from both lines are preserved in two
  groups with a provenance note.

Closes #1, closes #3
2026-07-05 00:23:48 +02:00

93 lines
5.0 KiB
Swift

@testable import PureYAML
import Testing
@Suite("Parsing Errors")
struct ParsingErrorTests {
@Test("Reports exact parser errors")
func test_errorReporting() {
expectParseError("root:\n child: yes\n wrong: no", .malformed(
reason: "while parsing a block mapping, did not find expected key",
line: 1,
column: 1,
))
expectParseError("- one\nkey: value", .malformed(
reason: "while parsing a block collection, did not find expected '-' indicator",
line: 1,
column: 1,
))
expectParseError("root:\n child: value\n dangling", .malformed(
reason: "while parsing a block mapping, did not find expected key",
line: 2,
column: 3,
))
expectParseError("name: \"open", .unterminatedQuotedString(line: 1))
expectParseError("name: 'open", .unterminatedQuotedString(line: 1))
expectParseError("second: *missing", .undefinedAlias(anchor: "missing", line: 1, column: 9))
expectParseError("%YAML 2.0\n---\nvalue: yes", .incompatibleYAMLDirective(line: 1))
expectParseError("value: !!int nope", .invalidTaggedScalar(
tag: "tag:yaml.org,2002:int",
value: "nope",
line: 1,
column: 8,
))
}
@Test("Parses empty and comment-only documents as null")
func test_emptyAndCommentOnlyDocumentsParseAsNull() throws {
#expect(try PureYAML.parse("") == .null)
#expect(try PureYAML.parse("# comment only") == .null)
#expect(try PureYAML.parse(" \n# comment only\n") == .null)
}
@Test("Rejects a tab used as block indentation")
func test_tabIndentationIsRejected() {
// YAML 1.2 forbids a tab from supplying block-structure indentation
// (spec rule s-indent is spaces only; libyaml scanner.c:1948-1953 refuses
// to consume a tab as whitespace where a simple key is allowed). The nested
// `child` mapping is indented by a tab, so the document must be rejected.
#expect(throws: PureYAML.Parsing.ParseError.self) {
try PureYAML.parse(
"""
root:
\tchild: value
""",
)
}
}
@Test("Parser errors describe returned failures")
func test_errorDescriptions() {
#expect(PureYAML.Parsing.ParseError.unexpectedIndentation(line: 3).description == "unexpected indentation at line 3")
#expect(PureYAML.Parsing.ParseError.mixedCollectionStyles(line: 4).description == "mapping and sequence entries are mixed at line 4")
#expect(PureYAML.Parsing.ParseError.expectedAnchorName(line: 6).description == "expected an anchor name at line 6")
#expect(PureYAML.Parsing.ParseError.expectedAliasName(line: 7).description == "expected an alias name at line 7")
#expect(PureYAML.Parsing.ParseError.unterminatedTag(line: 8).description == "unterminated tag at line 8")
#expect(PureYAML.Parsing.ParseError.unterminatedQuotedString(line: 9).description == "unterminated quoted string at line 9")
#expect(PureYAML.Parsing.ParseError.incompatibleYAMLDirective(line: 10).description == "incompatible YAML directive at line 10")
#expect(PureYAML.Parsing.ParseError.directiveWithoutDocument(line: 10).description == "directive is not followed by a document start at line 10")
#expect(PureYAML.Parsing.ParseError.unsupportedDirective(name: "%FOO", line: 10).description == "unsupported directive '%FOO' at line 10")
#expect(PureYAML.Parsing.ParseError.unsupportedMultiDocumentStream(line: 10).description == "multi-document streams are not supported at line 10")
#expect(PureYAML.Parsing.ParseError.expectedNode(line: 10, column: 2).description == "expected a YAML node at line 10, column 2")
#expect(PureYAML.Parsing.ParseError.expectedScalarKey(line: 11, column: 3).description == "expected a scalar mapping key at line 11, column 3")
#expect(PureYAML.Parsing.ParseError.undefinedAlias(anchor: "item", line: 12, column: 4).description == "undefined alias 'item' at line 12, column 4")
#expect(PureYAML.Parsing.ParseError.invalidTaggedScalar(
tag: "tag:yaml.org,2002:int",
value: "nope",
line: 13,
column: 5,
).description == "invalid scalar 'nope' for tag 'tag:yaml.org,2002:int' at line 13, column 5")
#expect(PureYAML.Parsing.ParseError.unexpectedEvent(
expected: "mapping key",
actual: "sequenceStart anchor=- tag=- style=flow @1:1@0",
line: 13,
column: 5,
).description == "expected mapping key at line 13, column 5, found sequenceStart anchor=- tag=- style=flow @1:1@0")
#expect(PureYAML.Parsing.ParseError.unexpectedToken(
expected: "stream end",
actual: "mappingKey",
line: 14,
column: 1,
).description == "expected stream end at line 14, column 1, found mappingKey")
}
}