Add ES2020 nodes

A whole standard just for power operator? ECMA must be kidding.

jasminesnake/__main__.py

@@ -10,7 +10,7 @@ import coloredlogs
 from jasminesnake import __version__, __snake__, LOG_LEVELS
 from .js_stream import JSBaseStream, JSStringStream, JSFileStream
 from .lex.ErrorListeners import LogErrorListener
-from ast import nodes, to_ascii_tree, from_parse_tree
+from .ast import to_ascii_tree, from_parse_tree
 
 
 def create_argument_parser():

jasminesnake/ast/__init__.py

@@ -4,14 +4,14 @@ from enum import Enum
 from typing import Union
 from antlr4 import ParseTreeWalker
 
-import lex.JavaScriptParser as Parser
+import jasminesnake.lex.JavaScriptParser as Parser
-import ast.nodes
+from . import nodes
 from .parse_tree_listeners import ASTListener
 
 JSP = Parser.JavaScriptParser
 
 
-def from_parse_tree(tree: JSP.ProgramContext) -> ast.nodes.Program:
+def from_parse_tree(tree: JSP.ProgramContext) -> nodes.Program:
     """Generate AST from ANTLR parse tree.
 
     Args:
@@ -26,7 +26,7 @@ def from_parse_tree(tree: JSP.ProgramContext) -> ast.nodes.Program:
 
 
 def to_ascii_tree(
-    node: Union[ast.nodes.Position, ast.nodes.SourceLocation, ast.nodes.Node],
+    node: Union[nodes.Position, nodes.SourceLocation, nodes.Node],
     name_prefix: str = "",
     nesting_lvl: int = 0,
 ):

jasminesnake/ast/nodes.py

@@ -8,20 +8,29 @@ The module lacks support of:
     * debugger statement
     * with statement
     * RegExp
- * ES6 features:
+ * ES2015 features:
     * generators/yield statement
     * for-of statement
     * template literals
-    * and other ES6 features :)
+ * ES2017 features:
+    * async/await.
+      Basically, the whole standard consists of it, so no ES2017 support.
+ * ES2018 features:
+    * for-await-of statement
+    * template literals
+ * ES2019 features
+    * catch binding omission.
+      The only ES2019 feature.
 
 More about ESTree standard:
 https://github.com/estree/estree/
 
 Todo:
     * Add support for lacking features
+    * Make another attempt to split up this module
 """
 
-from typing import List, Union, Optional, Literal as TypeLiteral, TypedDict, Any
+from typing import List, Union, Optional, Literal as TypeLiteral, Any
 from enum import Enum
 from collections import OrderedDict
 
@@ -30,8 +39,11 @@ from collections import OrderedDict
 
 # Custom types used in the nodes
 
-number = Union[int, float]
+number = float
-"""A type union consisting of int and float Python types. Consider it as Number type from JavaScript."""
+"""A type representing Number type in JavaScript."""
+
+bigint = int
+"""A type representing BigInt type in JavaScript."""
 
 SourceTypeLiteral = TypeLiteral["script", "module"]
 """The type for the `sourceType` field."""
@@ -42,6 +54,9 @@ VarDeclKind = TypeLiteral["var", "let", "const"]
 PropKind = TypeLiteral["init", "get", "set"]
 """A type for a `kind` field of `Property`."""
 
+MethodDefinitionKind = TypeLiteral["constructor", "method", "get", "set"]
+"""A type for a `kind` field of `MethodDefinition`."""
+
 
 class UnaryOperator(Enum):
     """A unary operator token."""
@@ -86,6 +101,7 @@ class BinaryOperator(Enum):
     AND = "&"
     IN = "in"
     INSTANCEOF = "instanceof"
+    POW = "**"
 
 
 class AssignmentOperator(Enum):
@@ -103,6 +119,7 @@ class AssignmentOperator(Enum):
     OR = "|="
     XOR = "^="
     AND = "&="
+    POW = "**="
 
 
 class LogicalOperator(Enum):
@@ -110,6 +127,7 @@ class LogicalOperator(Enum):
 
     OR = "||"
     AND = "&&"
+    NULLISH_COALESCING = "??"
 
 
 # Nodes forward declarations
@@ -145,6 +163,10 @@ class Identifier:
     ...
 
 
+class Literal:
+    ...
+
+
 # "Node objects" block
 
 
@@ -218,20 +240,6 @@ class Node:
         return self._fields
 
 
-# "Literal" block
-
-
-class Literal(Expression):
-    """A literal token. Note that a literal can be an expression."""
-
-    def __init__(
-        self, loc: Optional[SourceLocation], value: Union[str, bool, number, None]
-    ):
-        super().__init__("Literal", loc)
-        self.value = value
-        self._fields.update({"value": self.value})
-
-
 # "Programs" block
 
 
@@ -559,7 +567,11 @@ class ArrayExpression(Expression):
 class ObjectExpression(Expression):
     """An object expression."""
 
-    def __init__(self, loc: Optional[SourceLocation], properties: List[Property]):
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        properties: List[Union[Property, SpreadElement]],
+    ):
         super().__init__("ObjectExpression", loc)
         self.properties = properties
         self._fields.update({"properties": self.properties})
@@ -954,6 +966,9 @@ InExpression = _generate_binary_expression(BinaryOperator.IN, """An "in" express
 InstanceofExpression = _generate_binary_expression(
     BinaryOperator.INSTANCEOF, """An "instanceof" expression."""
 )
+PowBinaryExpression = _generate_binary_expression(
+    BinaryOperator.POW, """A power expression, e.g. ``2**3``."""
+)
 SimpleAssignExpression = _generate_assignment_expression(
     AssignmentOperator.ASSIGN, """An assignment done with operator ``=`` expression."""
 )
@@ -997,12 +1012,51 @@ AndAssignExpression = _generate_assignment_expression(
     AssignmentOperator.AND,
     """A "bit and" assignment done with operator ``&=`` expression.""",
 )
+PowAssignExpression = _generate_assignment_expression(
+    AssignmentOperator.POW, """A power assignment expression, e.g. ``x**=2``."""
+)
 OrLogicExpression = _generate_logical_expression(
     LogicalOperator.OR, """An "or" logical expression."""
 )
 AndLogicExpression = _generate_logical_expression(
     LogicalOperator.AND, """An "and" logical expression."""
 )
+NullishCoalescingLogicExpression = _generate_logical_expression(
+    LogicalOperator.NULLISH_COALESCING, """A nullish coalescing logical expression."""
+)
+
+
+# "Literal" block
+
+
+class Literal(Expression):
+    """A literal token. Note that a literal can be an expression."""
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        value: Union[str, bool, number, bigint, None],
+    ):
+        super().__init__("Literal", loc)
+        self.value = value
+        self._fields.update({"value": self.value})
+
+
+class BigIntLiteral(Literal):
+    """`bigint` property is the string representation of the ``BigInt`` value. It doesn't include the suffix ``n``.
+    In environments that don't support ``BigInt`` values, value property will be `None` as the ``BigInt`` value can't
+    be represented natively.
+    """
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        value: Union[str, bool, number, bigint, None],
+        bigint: str,
+    ):
+        super().__init__(loc, value)
+        self.bigint = bigint
+        self._fields.update({"bigint": self.bigint})
 
 
 # "Property" block
@@ -1016,7 +1070,7 @@ class Property(Node):
     def __init__(
         self,
         loc: Optional[SourceLocation],
-        key: Union[Literal, Identifier],
+        key: Expression,
         value: Expression,
         kind: PropKind,
         method: bool,
@@ -1046,7 +1100,7 @@ class AssignmentProperty(Property):
     def __init__(
         self,
         loc: Optional[SourceLocation],
-        key: Union[Literal, Identifier],
+        key: Expression,
         value: Pattern,
         shorthand: bool,
         computed: bool,
@@ -1067,14 +1121,18 @@ class Pattern(Node):
         super().__init__(node_type, loc)
 
 
-class ObjectPatternKeyValue(TypedDict):
+class RestElement(Pattern):
-    key: Union[Literal, Identifier]
+    def __init__(self, loc: Optional[SourceLocation], argument: Pattern):
-    value: Pattern
+        super().__init__("RestElement", loc)
+        self.argument = argument
+        self._fields.update({"argument": self.argument})
 
 
 class ObjectPattern(Pattern):
     def __init__(
-        self, loc: Optional[SourceLocation], properties: List[ObjectPatternKeyValue]
+        self,
+        loc: Optional[SourceLocation],
+        properties: List[Union[AssignmentProperty, RestElement]],
     ):
         super().__init__("ObjectPattern", loc)
         self.properties = properties
@@ -1090,6 +1148,14 @@ class ArrayPattern(Pattern):
         self._fields.update({"elements": self.elements})
 
 
+class AssignmentPattern(Pattern):
+    def __init__(self, loc: Optional[SourceLocation], left: Pattern, right: Expression):
+        super().__init__("AssignmentPattern", loc)
+        self.left = left
+        self.right = right
+        self._fields.update({"left": self.left, "right": self.right})
+
+
 # "Identifier" block
 
 
@@ -1099,3 +1165,281 @@ class Identifier(Expression, Pattern):
     def __init__(self, loc: Optional[SourceLocation], name: str):
         super().__init__("Identifier", loc)
         self.name = name
+        self._fields.update({"name": self.name})
+
+
+# "Classes" block
+
+
+class MethodDefinition(Node):
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        key: Expression,
+        value: FunctionExpression,
+        kind: MethodDefinitionKind,
+        computed: bool,
+        static: bool,
+    ):
+        super().__init__("MethodDefinition", loc)
+        self.key = key
+        self.value = value
+        self.kind = kind
+        self.computed = computed
+        self.static = static
+        self._fields.update(
+            {
+                "key": self.key,
+                "value": self.value,
+                "kind": self.kind,
+                "computed": self.computed,
+                "static": self.static,
+            }
+        )
+
+
+class ClassBody(Node):
+    def __init__(self, loc: Optional[SourceLocation], body: List[MethodDefinition]):
+        super().__init__("ClassBody", loc)
+        self.body = body
+        self._fields.update({"body": self.body})
+
+
+class Class(Node):
+    def __init__(
+        self,
+        node_type: str,
+        loc: Optional[SourceLocation],
+        class_id: Optional[Identifier],
+        super_class: Optional[Expression],
+        body: ClassBody,
+    ):
+        super().__init__(node_type, loc)
+        self.id = class_id
+        self.super_class = super_class
+        self.body = body
+        self._fields.update(
+            {"id": self.id, "superClass": self.super_class, "body": self.body}
+        )
+
+
+class ClassDeclaration(Class, Declaration):
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        class_id: Identifier,
+        super_class: Optional[Expression],
+        body: ClassBody,
+    ):
+        super().__init__("ClassDeclaration", loc, class_id, super_class, body)
+
+
+class ClassExpression(Class, Expression):
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        class_id: Optional[Identifier],
+        super_class: Optional[Expression],
+        body: ClassBody,
+    ):
+        super().__init__("ClassExpression", loc, class_id, super_class, body)
+
+
+class MetaProperty(Expression):
+    """`MetaProperty` node represents ``new.target`` meta property in ES2015.
+    In the future, it will represent other meta properties as well.
+    """
+
+    def __init__(
+        self, loc: Optional[SourceLocation], meta: Identifier, meta_property: Identifier
+    ):
+        super().__init__("MetaProperty", loc)
+        self.meta = (meta,)
+        self.property = meta_property
+        self._fields.update({"meta": self.meta, "property": self.property})
+
+
+# "Modules" block
+
+
+class ModuleDeclaration(Node):
+    """A module ``import`` or ``export`` declaration."""
+
+    def __init__(self, node_type: str, loc: Optional[SourceLocation]):
+        super().__init__(node_type, loc)
+
+
+class ModuleSpecifier(Node):
+    """A specifier in an import or export declaration."""
+
+    def __init__(
+        self, node_type: str, loc: Optional[SourceLocation], local: Identifier
+    ):
+        super().__init__(node_type, loc)
+        self.local = local
+        self._fields.update({"local": self.local})
+
+
+class ImportSpecifier(ModuleSpecifier):
+    """An imported variable binding, e.g., ``{foo}`` in ``import {foo} from "mod"``
+    or ``{foo as bar}`` in ``import {foo as bar} from "mod"``. The `imported` field
+    refers to the name of the export imported from the module. The `local` field
+    refers to the binding imported into the local module scope. If it is a basic named
+    import, such as in ``import {foo} from "mod"``, both `imported` and `local` are
+    equivalent `Identifier` nodes; in this case an `Identifier` node representing ``foo``.
+    If it is an aliased import, such as in ``import {foo as bar} from "mod"``, the
+    `imported` field is an `Identifier` node representing ``foo``, and the `local` field 
+    is an `Identifier` node representing ``bar``.
+    """
+
+    def __init__(
+        self, loc: Optional[SourceLocation], local: Identifier, imported: Identifier
+    ):
+        super().__init__("ImportSpecifier", loc, local)
+        self.imported = imported
+        self._fields.update({"imported": self.imported})
+
+
+class ImportDefaultSpecifier(ModuleSpecifier):
+    """A default import specifier, e.g., ``foo`` in ``import foo from "mod.js"``."""
+
+    def __init__(self, loc: Optional[SourceLocation], local: Identifier):
+        super().__init__("ImportDefaultSpecifier", loc, local)
+
+
+class ImportNamespaceSpecifier(ModuleSpecifier):
+    """A namespace import specifier, e.g., ``* as foo`` in ``import * as foo from "mod.js"``."""
+
+    def __init__(self, loc: Optional[SourceLocation], local: Identifier):
+        super().__init__("ImportNamespaceSpecifier", loc, local)
+
+
+class ImportDeclaration(ModuleDeclaration):
+    """An import declaration, e.g., ``import foo from "mod";``."""
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        specifiers: List[
+            Union[ImportSpecifier, ImportDefaultSpecifier, ImportNamespaceSpecifier]
+        ],
+        source: Literal,
+    ):
+        super().__init__("ImportDeclaration", loc)
+        self.specifiers = specifiers
+        self.source = source
+        self._fields.update({"specifiers": self.specifiers, "source": self.source})
+
+
+class ImportExpression(Expression):
+    """`ImportExpression` node represents Dynamic Imports such as ``import(source)``.
+    The `source` property is the importing source as similar to ImportDeclaration node,
+    but it can be an arbitrary expression node.
+    """
+
+    def __init__(self, loc: Optional[SourceLocation], source: Expression):
+        super().__init__("ImportExpression", loc)
+        self.source = source
+        self._fields.update({"source": self.source})
+
+
+class ExportSpecifier(ModuleSpecifier):
+    """An exported variable binding, e.g., ``{foo}`` in ``export {foo}`` or ``{bar as foo}``
+    in ``export {bar as foo}``. The `exported` field refers to the name exported in the module.
+    The `local` field refers to the binding into the local module scope. If it is a basic named
+    export, such as in ``export {foo}``, both `exported` and `local` are equivalent `Identifier`
+    nodes; in this case an `Identifier` node representing ``foo``. If it is an aliased export,
+    such as in ``export {bar as foo}``, the `exported` field is an `Identifier` node representing
+    ``foo``, and the `local` field is an `Identifier` node representing ``bar``.
+    """
+
+    def __init__(
+        self, loc: Optional[SourceLocation], local: Identifier, exported: Identifier
+    ):
+        super().__init__("ExportSpecifier", loc, local)
+        self.exported = exported
+        self._fields.update({"exported": self.exported})
+
+
+class ExportNamedDeclaration(ModuleDeclaration):
+    """An export named declaration, e.g., ``export {foo, bar};``, ``export {foo} from "mod";``
+    or ``export var foo = 1;``.
+
+    Notes:
+        Having `declaration` populated with non-empty `specifiers` or non-null `source` results
+        in an invalid state.
+    """
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        declaration: Optional[Declaration],
+        specifiers: List[ExportSpecifier],
+        source: Optional[Literal],
+    ):
+        super().__init__("ExportNamedDeclaration", loc)
+        self.declaration = declaration
+        self.specifiers = specifiers
+        self.source = source
+        self._fields.update(
+            {
+                "declaration": self.declaration,
+                "specifiers": self.specifiers,
+                "source": self.source,
+            }
+        )
+
+
+class AnonymousDefaultExportedFunctionDeclaration(Function):
+    def __init__(
+        self, loc: Optional[SourceLocation], params: List[Pattern], body: FunctionBody
+    ):
+        super().__init__("FunctionDeclaration", loc, None, params, body)
+
+
+class AnonymousDefaultExportedClassDeclaration(Class):
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        super_class: Optional[Expression],
+        body: ClassBody,
+    ):
+        super().__init__("ClassDeclaration", loc, None, super_class, body)
+
+
+class ExportDefaultDeclaration(ModuleDeclaration):
+    """An export default declaration, e.g., ``export default function () {};`` or ``export default 1;``."""
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        declaration: Union[
+            AnonymousDefaultExportedFunctionDeclaration,
+            FunctionDeclaration,
+            AnonymousDefaultExportedClassDeclaration,
+            ClassDeclaration,
+            Expression,
+        ],
+    ):
+        super().__init__("ExportDefaultDeclaration", loc)
+        self.declaration = declaration
+        self._fields.update({"declaration": self.declaration})
+
+
+class ExportAllDeclaration(ModuleDeclaration):
+    """An export batch declaration, e.g., ``export * from "mod";``.
+
+    The `exported` property contains an `Identifier` when a different exported 
+    name is specified using ``as``, e.g., ``export * as foo from "mod";``.
+    """
+
+    def __init__(
+        self,
+        loc: Optional[SourceLocation],
+        source: Literal,
+        exported: Optional[Identifier],
+    ):
+        super().__init__("ExportAllDeclaration", loc)
+        self.source = source
+        self.exported = exported
+        self._fields.update({"source": self.source, "exported": self.exported})

jasminesnake/ast/parse_tree_listeners.py

@@ -1,32 +1,38 @@
+"""Parse tree listeners.
+
+Basically, you should use ASTListener(source_type: SourceTypeLiteral) in most cases.
+
+Todo:
+    * Fill `source` field in SourceLocation and pass it to each `_get_source_location()` call.
+    * Compare `SourceLocation` creation behavior with the one in Acorn/ESPrima
+"""
 import logging
 from typing import Optional, List, Union
 import antlr4.ParserRuleContext
 
-from lex.JavaScriptParser import JavaScriptParser
+from ..lex.JavaScriptParser import JavaScriptParser
-from lex.JavaScriptParserListener import JavaScriptParserListener as JSBaseListener
+from ..lex.JavaScriptParserListener import JavaScriptParserListener as JSBaseListener
 
-import ast.nodes
+from . import nodes
 
 
 def _get_source_location(
     ctx: antlr4.ParserRuleContext, source: Optional[str]
-) -> ast.nodes.SourceLocation:
+) -> nodes.SourceLocation:
     """Internal function to obtain `SourceObject` from parser context."""
-    start_pos = ast.nodes.Position(ctx.start.line, ctx.start.column)
+    start_pos = nodes.Position(ctx.start.line, ctx.start.column)
-    end_pos = ast.nodes.Position(ctx.stop.line, ctx.stop.column)
+    end_pos = nodes.Position(ctx.stop.line, ctx.stop.column)
 
     # If an end is not on a newline, shift end position column by 1
     # to match exact token end, not the last character
     if end_pos.column != 0:
         end_pos.column += 1
 
-    return ast.nodes.SourceLocation(source=source, start=start_pos, end=end_pos)
+    return nodes.SourceLocation(source=source, start=start_pos, end=end_pos)
 
 
 class AssignableListener(JSBaseListener):
-    _result: Union[
+    _result: Union[nodes.Identifier, nodes.ObjectPattern, nodes.ArrayPattern]
-        ast.nodes.Identifier, ast.nodes.ObjectPattern, ast.nodes.ArrayPattern
-    ]
 
     @property
     def result(self):
@@ -39,19 +45,19 @@ class AssignableListener(JSBaseListener):
     def enterIdentifier(self, ctx: JavaScriptParser.IdentifierContext):
         logging.debug("Entered section Identifier")
         loc = _get_source_location(ctx, None)
-        self._result = ast.nodes.Identifier(loc, ctx.getText())
+        self._result = nodes.Identifier(loc, ctx.getText())
 
     def enterArrayLiteral(self, ctx: JavaScriptParser.ArrayLiteralContext):
         logging.debug("Entered section ArrayLiteral")
-        pass  # TODO
+        raise NotImplementedError("ArrayLiteral assignment")  # TODO
 
     def enterObjectLiteral(self, ctx: JavaScriptParser.ObjectLiteralContext):
         logging.debug("Entered section ObjectLiteral")
-        pass  # TODO
+        raise NotImplementedError("ObjectLiteral assignment")  # TODO
 
 
 class VariableDeclarationListener(JSBaseListener):
-    _var_decl: ast.nodes.VariableDeclarator
+    _var_decl: nodes.VariableDeclarator
 
     @property
     def var_declarator(self):
@@ -63,17 +69,21 @@ class VariableDeclarationListener(JSBaseListener):
         loc = _get_source_location(ctx, None)
         assign_listener = AssignableListener()
         ctx.assignable().enterRule(assign_listener)
+
+        if ctx.singleExpression() is not None:
+            raise NotImplementedError("VariableDeclarator initialization")
+
         # ctx.singleExpression().enterRule(expression_listener)  # FIXME No ExpressionListener yet
-        self._var_decl = ast.nodes.VariableDeclarator(
+        init = None  # value from ExpressionListener
-            loc, assign_listener.result, None
+
-        )  # FIXME
+        self._var_decl = nodes.VariableDeclarator(loc, assign_listener.result, init)
 
 
 class StatementListener(JSBaseListener):
-    _stmt: ast.nodes.Statement
+    _stmt: nodes.Statement
 
     @property
-    def statement(self) -> ast.nodes.Statement:
+    def statement(self) -> nodes.Statement:
         """Statement AST node generated after parse tree walking."""
 
         return self._stmt
@@ -87,14 +97,14 @@ class StatementListener(JSBaseListener):
         """Listener for BlockStatement."""
         logging.debug("Entered section Block")
 
-        stmt_list: List[ast.nodes.Statement] = []
+        stmt_list: List[nodes.Statement] = []
         for stmt in ctx.statementList().children:
             stmt_listener = StatementListener()
             stmt.enterRule(stmt_listener)
             stmt_list.append(stmt_listener.statement)
 
-        loc = _get_source_location(ctx, None)  # FIXME source param is None
+        loc = _get_source_location(ctx, None)
-        self._stmt = ast.nodes.BlockStatement(loc, stmt_list)
+        self._stmt = nodes.BlockStatement(loc, stmt_list)
 
     def enterVariableStatement(self, ctx: JavaScriptParser.VariableStatementContext):
         logging.debug("Entered section VariableStatement")
@@ -106,8 +116,8 @@ class StatementListener(JSBaseListener):
         """Listener for VariableDeclaration."""
         logging.debug("Entered section VariableDeclaration")
 
-        var_modifier: ast.nodes.VarDeclKind = ctx.varModifier().getText()
+        var_modifier: nodes.VarDeclKind = ctx.varModifier().getText()
-        var_decls: List[ast.nodes.VariableDeclarator] = []
+        var_decls: List[nodes.VariableDeclarator] = []
 
         for var_decl in ctx.variableDeclaration():
             var_decl_listener = VariableDeclarationListener()
@@ -115,11 +125,13 @@ class StatementListener(JSBaseListener):
             var_decls.append(var_decl_listener.var_declarator)
 
         loc = _get_source_location(ctx, None)
-        self._stmt = ast.nodes.VariableDeclaration(loc, var_modifier, var_decls)
+        self._stmt = nodes.VariableDeclaration(loc, var_modifier, var_decls)
 
     def enterEmptyStatement(self, ctx: JavaScriptParser.EmptyStatementContext):
         """Listener for EmptyStatement."""
         logging.debug("Entered section EmptyStatement")
+        loc = _get_source_location(ctx, None)
+        self._stmt = nodes.EmptyStatement(loc)
         pass
 
     def enterExpressionStatement(
@@ -129,11 +141,12 @@ class StatementListener(JSBaseListener):
         TODO: check up expression containers.
         """
         logging.debug("Entered section ExpressionStatement")
-        pass
+        raise NotImplementedError("ExpressionStatement")
 
     def enterIfStatement(self, ctx: JavaScriptParser.IfStatementContext):
         """Listener for IfStatement."""
         logging.debug("Entered section IfStatement")
+        raise NotImplementedError("ExpressionStatement")  # FIXME
         pass
 
     def enterFunctionDeclaration(
@@ -141,7 +154,7 @@ class StatementListener(JSBaseListener):
     ):
         """Listener for FunctionDeclaration."""
         logging.debug("Entered section FunctionDeclaration")
-        pass
+        raise NotImplementedError("FunctionDeclaration")
 
     # TODO: import/export, ClassDeclaration, iter statements, continue. break, return
 
@@ -149,10 +162,10 @@ class StatementListener(JSBaseListener):
 class SourceElementListener(JSBaseListener):
     """The proxy between Program and Statement."""
 
-    _elems: List[ast.nodes.Statement] = []
+    _elems: List[nodes.Statement] = []
 
     @property
-    def source_elements(self) -> List[ast.nodes.Statement]:
+    def source_elements(self) -> List[nodes.Statement]:
         """Source elements AST nodes generated after parse tree walking."""
 
         return self._elems
@@ -168,22 +181,22 @@ class SourceElementListener(JSBaseListener):
 class ASTListener(JSBaseListener):
     """AST listener."""
 
-    _program_node: Optional[ast.nodes.Program] = None
+    _program_node: Optional[nodes.Program] = None
-    _source_type: ast.nodes.SourceTypeLiteral
+    _source_type: nodes.SourceTypeLiteral
 
     @property
-    def program_node(self) -> ast.nodes.Program:
+    def program_node(self) -> nodes.Program:
         """The `Program` AST node generated after parse tree walking."""
         if self._program_node is None:
             raise ValueError("Program AST node is None, did you run the listener?")
 
         return self._program_node
 
-    def __init__(self, source_type: ast.nodes.SourceTypeLiteral = "script"):
+    def __init__(self, source_type: nodes.SourceTypeLiteral = "script"):
         """AST listener constructor.
 
         Args:
-            source_type (ast.nodes.SourceTypeLiteral): source type. Could be `script` or `module`. Set to
+            source_type (nodes.SourceTypeLiteral): source type. Could be `script` or `module`. Set to
                 `script` by default.
         """
         self._source_type = source_type
@@ -204,6 +217,6 @@ class ASTListener(JSBaseListener):
             elem.enterRule(source_elem_listener)
 
         loc = _get_source_location(ctx, None)  # FIXME add source name
-        self._program_node = ast.nodes.Program(
+        self._program_node = nodes.Program(
             loc, self._source_type, source_elem_listener.source_elements
         )

jasminesnake/lex/.gitignore

@@ -0,0 +1,6 @@
+*
+!.gitignore
+!JavaScriptBaseLexer.py
+!JavaScriptBaseParser.py
+!ErrorListeners.py
+!__init__.py

jasminesnake/lex/__init__.py

@@ -0,0 +1,3 @@
+"""Lexer/parser module.
+Consists mostly of auto-generated files spewed by ANTLR.
+"""