Mihaela Mihaljevic
f7fe89023c
Add the PureXML.Pattern namespace: a compiler for the streamable XPath subset (names, *, prefix:*, /, //, leading absolute /, trailing @attr) into a Matcher, with predicates and . / .. rejected. The backward-matching algorithm tests an element's ancestor-or-self path. Pattern.matches(_:in:) streams a document through the pull parser and returns matching node paths in document order from the open-element stack alone, no tree built. Closes #44 Closes #45 Closes #22
84 lines
2.6 KiB
Swift
84 lines
2.6 KiB
Swift
@testable import PureXML
|
|
import Testing
|
|
|
|
@Suite("Streaming patterns")
|
|
struct PatternTests {
|
|
private let xml = "<r>"
|
|
+ "<a id=\"1\"><b><c/></b></a>"
|
|
+ "<a id=\"2\"><b/></a>"
|
|
+ "<d><b/></d>"
|
|
+ "</r>"
|
|
|
|
private func match(_ pattern: String) throws -> [String] {
|
|
try PureXML.Pattern.matches(pattern, in: xml)
|
|
}
|
|
|
|
@Test("A relative name matches that element at any depth")
|
|
func test_relativeName() throws {
|
|
#expect(try match("b") == ["/r/a/b", "/r/a/b", "/r/d/b"])
|
|
}
|
|
|
|
@Test("A child path requires the immediate parent")
|
|
func test_childPath() throws {
|
|
#expect(try match("a/b") == ["/r/a/b", "/r/a/b"])
|
|
}
|
|
|
|
@Test("An absolute path is anchored at the root")
|
|
func test_absolutePath() throws {
|
|
#expect(try match("/r/a/b") == ["/r/a/b", "/r/a/b"])
|
|
#expect(try match("/a/b").isEmpty)
|
|
}
|
|
|
|
@Test("A descendant step matches at any depth below")
|
|
func test_descendant() throws {
|
|
#expect(try match("a//c") == ["/r/a/b/c"])
|
|
#expect(try match("//c") == ["/r/a/b/c"])
|
|
}
|
|
|
|
@Test("The wildcard matches any element name")
|
|
func test_wildcard() throws {
|
|
#expect(try match("r/*") == ["/r/a", "/r/a", "/r/d"])
|
|
}
|
|
|
|
@Test("An attribute pattern matches attributes of matching elements")
|
|
func test_attributePattern() throws {
|
|
#expect(try match("a/@id") == ["/r/a/@id", "/r/a/@id"])
|
|
#expect(try match("//@id") == ["/r/a/@id", "/r/a/@id"])
|
|
}
|
|
|
|
@Test("A non-matching pattern yields nothing")
|
|
func test_noMatch() throws {
|
|
#expect(try match("x").isEmpty)
|
|
#expect(try match("d/c").isEmpty)
|
|
}
|
|
|
|
@Test("The compiled matcher tests an explicit path")
|
|
func test_explicitPath() throws {
|
|
let matcher = try PureXML.Pattern.Matcher("a/b")
|
|
let path = [
|
|
PureXML.Model.QualifiedName("r"),
|
|
PureXML.Model.QualifiedName("a"),
|
|
PureXML.Model.QualifiedName("b"),
|
|
]
|
|
#expect(matcher.matchesElement(path: path))
|
|
#expect(!matcher.matchesElement(path: Array(path.dropLast())))
|
|
}
|
|
|
|
@Test("Predicates and parent steps are rejected as unsupported")
|
|
func test_unsupported() {
|
|
#expect(throws: PureXML.Pattern.PatternError.self) {
|
|
_ = try PureXML.Pattern.Matcher("a[1]")
|
|
}
|
|
#expect(throws: PureXML.Pattern.PatternError.self) {
|
|
_ = try PureXML.Pattern.Matcher("..")
|
|
}
|
|
}
|
|
|
|
@Test("An empty pattern is rejected")
|
|
func test_empty() {
|
|
#expect(throws: PureXML.Pattern.PatternError.empty) {
|
|
_ = try PureXML.Pattern.Matcher("")
|
|
}
|
|
}
|
|
}
|