import { AST_Array, AST_Atom, AST_Await, AST_BigInt, AST_Binary, AST_Block, AST_Call, AST_Catch, AST_Chain, AST_Class, AST_ClassProperty, AST_ConciseMethod, AST_Conditional, AST_Debugger, AST_Definitions, AST_Destructuring, AST_Directive, AST_Do, AST_Dot, AST_EmptyStatement, AST_Expansion, AST_Export, AST_Finally, AST_For, AST_ForIn, AST_ForOf, AST_If, AST_Import, AST_ImportMeta, AST_Jump, AST_LabeledStatement, AST_Lambda, AST_LoopControl, AST_NameMapping, AST_NewTarget, AST_Node, AST_Number, AST_Object, AST_ObjectGetter, AST_ObjectKeyVal, AST_ObjectProperty, AST_ObjectSetter, AST_PrefixedTemplateString, AST_PropAccess, AST_RegExp, AST_Sequence, AST_SimpleStatement, AST_String, AST_Super, AST_Switch, AST_SwitchBranch, AST_Symbol, AST_TemplateSegment, AST_TemplateString, AST_This, AST_Toplevel, AST_Try, AST_Unary, AST_VarDef, AST_While, AST_With, AST_Yield } from "./ast.js"; const shallow_cmp = (node1, node2) => { return ( node1 === null && node2 === null || node1.TYPE === node2.TYPE && node1.shallow_cmp(node2) ); }; export const equivalent_to = (tree1, tree2) => { if (!shallow_cmp(tree1, tree2)) return false; const walk_1_state = [tree1]; const walk_2_state = [tree2]; const walk_1_push = walk_1_state.push.bind(walk_1_state); const walk_2_push = walk_2_state.push.bind(walk_2_state); while (walk_1_state.length && walk_2_state.length) { const node_1 = walk_1_state.pop(); const node_2 = walk_2_state.pop(); if (!shallow_cmp(node_1, node_2)) return false; node_1._children_backwards(walk_1_push); node_2._children_backwards(walk_2_push); if (walk_1_state.length !== walk_2_state.length) { // Different number of children return false; } } return walk_1_state.length == 0 && walk_2_state.length == 0; }; // Creates a shallow compare function const mkshallow = (props) => { const comparisons = Object .keys(props) .map(key => { if (props[key] === "eq") { return `this.${key} === other.${key}`; } else if (props[key] === "exist") { return `(this.${key} == null ? other.${key} == null : this.${key} === other.${key})`; } else { throw new Error(`mkshallow: Unexpected instruction: ${props[key]}`); } }) .join(" && "); return new Function("other", "return " + comparisons); }; const pass_through = () => true; AST_Node.prototype.shallow_cmp = function () { throw new Error("did not find a shallow_cmp function for " + this.constructor.name); }; AST_Debugger.prototype.shallow_cmp = pass_through; AST_Directive.prototype.shallow_cmp = mkshallow({ value: "eq" }); AST_SimpleStatement.prototype.shallow_cmp = pass_through; AST_Block.prototype.shallow_cmp = pass_through; AST_EmptyStatement.prototype.shallow_cmp = pass_through; AST_LabeledStatement.prototype.shallow_cmp = mkshallow({ "label.name": "eq" }); AST_Do.prototype.shallow_cmp = pass_through; AST_While.prototype.shallow_cmp = pass_through; AST_For.prototype.shallow_cmp = mkshallow({ init: "exist", condition: "exist", step: "exist" }); AST_ForIn.prototype.shallow_cmp = pass_through; AST_ForOf.prototype.shallow_cmp = pass_through; AST_With.prototype.shallow_cmp = pass_through; AST_Toplevel.prototype.shallow_cmp = pass_through; AST_Expansion.prototype.shallow_cmp = pass_through; AST_Lambda.prototype.shallow_cmp = mkshallow({ is_generator: "eq", async: "eq" }); AST_Destructuring.prototype.shallow_cmp = mkshallow({ is_array: "eq" }); AST_PrefixedTemplateString.prototype.shallow_cmp = pass_through; AST_TemplateString.prototype.shallow_cmp = pass_through; AST_TemplateSegment.prototype.shallow_cmp = mkshallow({ "value": "eq" }); AST_Jump.prototype.shallow_cmp = pass_through; AST_LoopControl.prototype.shallow_cmp = pass_through; AST_Await.prototype.shallow_cmp = pass_through; AST_Yield.prototype.shallow_cmp = mkshallow({ is_star: "eq" }); AST_If.prototype.shallow_cmp = mkshallow({ alternative: "exist" }); AST_Switch.prototype.shallow_cmp = pass_through; AST_SwitchBranch.prototype.shallow_cmp = pass_through; AST_Try.prototype.shallow_cmp = mkshallow({ bcatch: "exist", bfinally: "exist" }); AST_Catch.prototype.shallow_cmp = mkshallow({ argname: "exist" }); AST_Finally.prototype.shallow_cmp = pass_through; AST_Definitions.prototype.shallow_cmp = pass_through; AST_VarDef.prototype.shallow_cmp = mkshallow({ value: "exist" }); AST_NameMapping.prototype.shallow_cmp = pass_through; AST_Import.prototype.shallow_cmp = mkshallow({ imported_name: "exist", imported_names: "exist" }); AST_ImportMeta.prototype.shallow_cmp = pass_through; AST_Export.prototype.shallow_cmp = mkshallow({ exported_definition: "exist", exported_value: "exist", exported_names: "exist", module_name: "eq", is_default: "eq", }); AST_Call.prototype.shallow_cmp = pass_through; AST_Sequence.prototype.shallow_cmp = pass_through; AST_PropAccess.prototype.shallow_cmp = pass_through; AST_Chain.prototype.shallow_cmp = pass_through; AST_Dot.prototype.shallow_cmp = mkshallow({ property: "eq" }); AST_Unary.prototype.shallow_cmp = mkshallow({ operator: "eq" }); AST_Binary.prototype.shallow_cmp = mkshallow({ operator: "eq" }); AST_Conditional.prototype.shallow_cmp = pass_through; AST_Array.prototype.shallow_cmp = pass_through; AST_Object.prototype.shallow_cmp = pass_through; AST_ObjectProperty.prototype.shallow_cmp = pass_through; AST_ObjectKeyVal.prototype.shallow_cmp = mkshallow({ key: "eq" }); AST_ObjectSetter.prototype.shallow_cmp = mkshallow({ static: "eq" }); AST_ObjectGetter.prototype.shallow_cmp = mkshallow({ static: "eq" }); AST_ConciseMethod.prototype.shallow_cmp = mkshallow({ static: "eq", is_generator: "eq", async: "eq", }); AST_Class.prototype.shallow_cmp = mkshallow({ name: "exist", extends: "exist", }); AST_ClassProperty.prototype.shallow_cmp = mkshallow({ static: "eq" }); AST_Symbol.prototype.shallow_cmp = mkshallow({ name: "eq" }); AST_NewTarget.prototype.shallow_cmp = pass_through; AST_This.prototype.shallow_cmp = pass_through; AST_Super.prototype.shallow_cmp = pass_through; AST_String.prototype.shallow_cmp = mkshallow({ value: "eq" }); AST_Number.prototype.shallow_cmp = mkshallow({ value: "eq" }); AST_BigInt.prototype.shallow_cmp = mkshallow({ value: "eq" }); AST_RegExp.prototype.shallow_cmp = function (other) { return ( this.value.flags === other.value.flags && this.value.source === other.value.source ); }; AST_Atom.prototype.shallow_cmp = pass_through;