perf: introduce AST to avoid reparse

test/unit/parser/parse-string-literal.ts

@@ -0,0 +1,35 @@
+import { expect } from 'chai'
+import { parseStringLiteral } from '../../../src/parser/parse-string-literal'
+
+describe('parseStringLiteral()', function () {
+  it('should parse octal escape', () => {
+    expect(parseStringLiteral(String.raw`"\1010"`)).to.equal('A0')
+    expect(parseStringLiteral(String.raw`"\12"`)).to.equal('\n')
+    expect(parseStringLiteral(String.raw`"\01"`)).to.equal('\u0001')
+    expect(parseStringLiteral(String.raw`"\0"`)).to.equal('\0')
+  })
+  it('should skip invalid octal escape', () => {
+    expect(parseStringLiteral(String.raw`"\9"`)).to.equal('9')
+  })
+  it('should parse \\n, \\t, \\r', () => {
+    expect(parseStringLiteral(String.raw`"fo\no"`)).to.equal('fo\no')
+    expect(parseStringLiteral(String.raw`'fo\to'`)).to.equal('fo\to')
+    expect(parseStringLiteral(String.raw`'fo\ro'`)).to.equal('fo\ro')
+  })
+  it('should parse unicode(hex) escape', () => {
+    expect(parseStringLiteral('"\\u003C"')).to.equal('<')
+    expect(parseStringLiteral('"\\u003cZ"')).to.equal('<Z')
+    expect(parseStringLiteral('"\\u41"')).to.equal('A')
+  })
+  it('should skip invalid unicode(hex) escape', () => {
+    expect(parseStringLiteral('"\\u41Z"')).to.equal('AZ')
+    expect(parseStringLiteral('"\\uZ"')).to.equal('\0Z')
+  })
+  it('should parse quote escape', () => {
+    expect(parseStringLiteral(String.raw`"fo\'o"`)).to.equal("fo'o")
+    expect(parseStringLiteral(String.raw`'fo\"o'`)).to.equal('fo"o')
+  })
+  it('should parse slash escape', () => {
+    expect(parseStringLiteral(String.raw`'fo\\o'`)).to.equal('fo\\o')
+  })
+})