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alert / js / node_modules / @babel / helper-module-transforms / lib / rewrite-live-references.js
@Réz István Réz István on 18 Nov 2021 9 KB first commit
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = rewriteLiveReferences;

var _assert = require("assert");

var t = require("@babel/types");

var _template = require("@babel/template");

var _helperSimpleAccess = require("@babel/helper-simple-access");

function rewriteLiveReferences(programPath, metadata) {
  const imported = new Map();
  const exported = new Map();

  const requeueInParent = path => {
    programPath.requeue(path);
  };

  for (const [source, data] of metadata.source) {
    for (const [localName, importName] of data.imports) {
      imported.set(localName, [source, importName, null]);
    }

    for (const localName of data.importsNamespace) {
      imported.set(localName, [source, null, localName]);
    }
  }

  for (const [local, data] of metadata.local) {
    let exportMeta = exported.get(local);

    if (!exportMeta) {
      exportMeta = [];
      exported.set(local, exportMeta);
    }

    exportMeta.push(...data.names);
  }

  const rewriteBindingInitVisitorState = {
    metadata,
    requeueInParent,
    scope: programPath.scope,
    exported
  };
  programPath.traverse(rewriteBindingInitVisitor, rewriteBindingInitVisitorState);
  (0, _helperSimpleAccess.default)(programPath, new Set([...Array.from(imported.keys()), ...Array.from(exported.keys())]));
  const rewriteReferencesVisitorState = {
    seen: new WeakSet(),
    metadata,
    requeueInParent,
    scope: programPath.scope,
    imported,
    exported,
    buildImportReference: ([source, importName, localName], identNode) => {
      const meta = metadata.source.get(source);

      if (localName) {
        if (meta.lazy) identNode = t.callExpression(identNode, []);
        return identNode;
      }

      let namespace = t.identifier(meta.name);
      if (meta.lazy) namespace = t.callExpression(namespace, []);

      if (importName === "default" && meta.interop === "node-default") {
        return namespace;
      }

      const computed = metadata.stringSpecifiers.has(importName);
      return t.memberExpression(namespace, computed ? t.stringLiteral(importName) : t.identifier(importName), computed);
    }
  };
  programPath.traverse(rewriteReferencesVisitor, rewriteReferencesVisitorState);
}

const rewriteBindingInitVisitor = {
  Scope(path) {
    path.skip();
  },

  ClassDeclaration(path) {
    const {
      requeueInParent,
      exported,
      metadata
    } = this;
    const {
      id
    } = path.node;
    if (!id) throw new Error("Expected class to have a name");
    const localName = id.name;
    const exportNames = exported.get(localName) || [];

    if (exportNames.length > 0) {
      const statement = t.expressionStatement(buildBindingExportAssignmentExpression(metadata, exportNames, t.identifier(localName)));
      statement._blockHoist = path.node._blockHoist;
      requeueInParent(path.insertAfter(statement)[0]);
    }
  },

  VariableDeclaration(path) {
    const {
      requeueInParent,
      exported,
      metadata
    } = this;
    Object.keys(path.getOuterBindingIdentifiers()).forEach(localName => {
      const exportNames = exported.get(localName) || [];

      if (exportNames.length > 0) {
        const statement = t.expressionStatement(buildBindingExportAssignmentExpression(metadata, exportNames, t.identifier(localName)));
        statement._blockHoist = path.node._blockHoist;
        requeueInParent(path.insertAfter(statement)[0]);
      }
    });
  }

};

const buildBindingExportAssignmentExpression = (metadata, exportNames, localExpr) => {
  return (exportNames || []).reduce((expr, exportName) => {
    const {
      stringSpecifiers
    } = metadata;
    const computed = stringSpecifiers.has(exportName);
    return t.assignmentExpression("=", t.memberExpression(t.identifier(metadata.exportName), computed ? t.stringLiteral(exportName) : t.identifier(exportName), computed), expr);
  }, localExpr);
};

const buildImportThrow = localName => {
  return _template.default.expression.ast`
    (function() {
      throw new Error('"' + '${localName}' + '" is read-only.');
    })()
  `;
};

const rewriteReferencesVisitor = {
  ReferencedIdentifier(path) {
    const {
      seen,
      buildImportReference,
      scope,
      imported,
      requeueInParent
    } = this;
    if (seen.has(path.node)) return;
    seen.add(path.node);
    const localName = path.node.name;
    const importData = imported.get(localName);

    if (importData) {
      const localBinding = path.scope.getBinding(localName);
      const rootBinding = scope.getBinding(localName);
      if (rootBinding !== localBinding) return;
      const ref = buildImportReference(importData, path.node);
      ref.loc = path.node.loc;

      if ((path.parentPath.isCallExpression({
        callee: path.node
      }) || path.parentPath.isOptionalCallExpression({
        callee: path.node
      }) || path.parentPath.isTaggedTemplateExpression({
        tag: path.node
      })) && t.isMemberExpression(ref)) {
        path.replaceWith(t.sequenceExpression([t.numericLiteral(0), ref]));
      } else if (path.isJSXIdentifier() && t.isMemberExpression(ref)) {
        const {
          object,
          property
        } = ref;
        path.replaceWith(t.jsxMemberExpression(t.jsxIdentifier(object.name), t.jsxIdentifier(property.name)));
      } else {
        path.replaceWith(ref);
      }

      requeueInParent(path);
      path.skip();
    }
  },

  AssignmentExpression: {
    exit(path) {
      const {
        scope,
        seen,
        imported,
        exported,
        requeueInParent,
        buildImportReference
      } = this;
      if (seen.has(path.node)) return;
      seen.add(path.node);
      const left = path.get("left");
      if (left.isMemberExpression()) return;

      if (left.isIdentifier()) {
        const localName = left.node.name;

        if (scope.getBinding(localName) !== path.scope.getBinding(localName)) {
          return;
        }

        const exportedNames = exported.get(localName);
        const importData = imported.get(localName);

        if ((exportedNames == null ? void 0 : exportedNames.length) > 0 || importData) {
          _assert(path.node.operator === "=", "Path was not simplified");

          const assignment = path.node;

          if (importData) {
            assignment.left = buildImportReference(importData, assignment.left);
            assignment.right = t.sequenceExpression([assignment.right, buildImportThrow(localName)]);
          }

          path.replaceWith(buildBindingExportAssignmentExpression(this.metadata, exportedNames, assignment));
          requeueInParent(path);
        }
      } else {
        const ids = left.getOuterBindingIdentifiers();
        const programScopeIds = Object.keys(ids).filter(localName => scope.getBinding(localName) === path.scope.getBinding(localName));
        const id = programScopeIds.find(localName => imported.has(localName));

        if (id) {
          path.node.right = t.sequenceExpression([path.node.right, buildImportThrow(id)]);
        }

        const items = [];
        programScopeIds.forEach(localName => {
          const exportedNames = exported.get(localName) || [];

          if (exportedNames.length > 0) {
            items.push(buildBindingExportAssignmentExpression(this.metadata, exportedNames, t.identifier(localName)));
          }
        });

        if (items.length > 0) {
          let node = t.sequenceExpression(items);

          if (path.parentPath.isExpressionStatement()) {
            node = t.expressionStatement(node);
            node._blockHoist = path.parentPath.node._blockHoist;
          }

          const statement = path.insertAfter(node)[0];
          requeueInParent(statement);
        }
      }
    }

  },

  "ForOfStatement|ForInStatement"(path) {
    const {
      scope,
      node
    } = path;
    const {
      left
    } = node;
    const {
      exported,
      imported,
      scope: programScope
    } = this;

    if (!t.isVariableDeclaration(left)) {
      let didTransformExport = false,
          importConstViolationName;
      const loopBodyScope = path.get("body").scope;

      for (const name of Object.keys(t.getOuterBindingIdentifiers(left))) {
        if (programScope.getBinding(name) === scope.getBinding(name)) {
          if (exported.has(name)) {
            didTransformExport = true;

            if (loopBodyScope.hasOwnBinding(name)) {
              loopBodyScope.rename(name);
            }
          }

          if (imported.has(name) && !importConstViolationName) {
            importConstViolationName = name;
          }
        }
      }

      if (!didTransformExport && !importConstViolationName) {
        return;
      }

      path.ensureBlock();
      const bodyPath = path.get("body");
      const newLoopId = scope.generateUidIdentifierBasedOnNode(left);
      path.get("left").replaceWith(t.variableDeclaration("let", [t.variableDeclarator(t.cloneNode(newLoopId))]));
      scope.registerDeclaration(path.get("left"));

      if (didTransformExport) {
        bodyPath.unshiftContainer("body", t.expressionStatement(t.assignmentExpression("=", left, newLoopId)));
      }

      if (importConstViolationName) {
        bodyPath.unshiftContainer("body", t.expressionStatement(buildImportThrow(importConstViolationName)));
      }
    }
  }

};