Python IncrementalLexer.relexの例

コード例 #1

ファイル: test_inclexer.py プロジェクト: Britefury/eco

    def test_backwards_lexing(self):
        lexer = IncrementalLexer("""
"::=":doublecolon
"=":equal
":":singlecolon
        """)
        ast = AST()
        ast.init()
        bos = ast.parent.children[0]
        eos = ast.parent.children[1]
        text = TextNode(Terminal(":"))
        bos.insert_after(text)
        lexer.relex(text)

        assert bos.next_term.symbol.name == ":"
        assert bos.next_term.lookup == "singlecolon"
        assert text.lookahead == 1

        text2 = TextNode(Terminal(":"))
        text.insert_after(text2)
        lexer.relex(text2)
        assert text2.lookahead == 1

        assert bos.next_term.symbol.name == ":"
        assert bos.next_term.next_term.symbol.name == ":"

        text3 = TextNode(Terminal("="))
        text2.insert_after(text3)
        lexer.relex(text3)

        assert bos.next_term.symbol.name == "::="
        assert isinstance(bos.next_term.next_term, EOS)

コード例 #2

ファイル: test_inclexer.py プロジェクト: beardhatcode/eco

    def test_backwards_lexing(self):
        lexer = IncrementalLexer("""
"::=":doublecolon
"=":equal
":":singlecolon
        """)
        ast = AST()
        ast.init()
        bos = ast.parent.children[0]
        eos = ast.parent.children[1]
        text = TextNode(Terminal(":"))
        bos.insert_after(text)
        lexer.relex(text)

        assert bos.next_term.symbol.name == ":"
        assert bos.next_term.lookup == "singlecolon"
        assert text.lookahead == 1

        text2 = TextNode(Terminal(":"))
        text.insert_after(text2)
        lexer.relex(text2)
        assert text2.lookahead == 1

        assert bos.next_term.symbol.name == ":"
        assert bos.next_term.next_term.symbol.name == ":"

        text3 = TextNode(Terminal("="))
        text2.insert_after(text3)
        lexer.relex(text3)

        assert bos.next_term.symbol.name == "::="
        assert isinstance(bos.next_term.next_term, EOS)

コード例 #3

ファイル: test_inclexer.py プロジェクト: Britefury/eco

    def test_lookahead(self):
        lexer = IncrementalLexer("""
"aaa":aaa
"a":a
"b":b
        """)
        ast = AST()
        ast.init()
        bos = ast.parent.children[0]
        eos = ast.parent.children[1]
        text = TextNode(Terminal("baab"))
        bos.insert_after(text)
        lexer.relex(text)
        assert ast.parent.children[1].symbol.name == "b"
        assert ast.parent.children[2].symbol.name == "a"
        assert ast.parent.children[3].symbol.name == "a"
        assert ast.parent.children[4].symbol.name == "b"
        ast.parent.children[1].symbol = None
        ast.parent.children[3].symbol.name = "aa"
        lexer.relex(ast.parent.children[3])

        assert ast.parent.children[2].symbol.name == "aaa"
        assert ast.parent.children[3].symbol.name == "b"

コード例 #4

ファイル: test_inclexer.py プロジェクト: beardhatcode/eco

    def test_lookahead(self):
        lexer = IncrementalLexer("""
"aaa":aaa
"a":a
"b":b
        """)
        ast = AST()
        ast.init()
        bos = ast.parent.children[0]
        eos = ast.parent.children[1]
        text = TextNode(Terminal("baab"))
        bos.insert_after(text)
        lexer.relex(text)
        assert ast.parent.children[1].symbol.name == "b"
        assert ast.parent.children[2].symbol.name == "a"
        assert ast.parent.children[3].symbol.name == "a"
        assert ast.parent.children[4].symbol.name == "b"
        ast.parent.children[1].symbol = None
        ast.parent.children[3].symbol.name = "aa"
        lexer.relex(ast.parent.children[3])

        assert ast.parent.children[2].symbol.name == "aaa"
        assert ast.parent.children[3].symbol.name == "b"