WIP - add extractor, generate snippet_data

node_modules/@babel/plugin-transform-parameters/lib/params.js

@@ -0,0 +1,167 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = convertFunctionParams;
+
+function _helperCallDelegate() {
+  const data = _interopRequireDefault(require("@babel/helper-call-delegate"));
+
+  _helperCallDelegate = function () {
+    return data;
+  };
+
+  return data;
+}
+
+function _core() {
+  const data = require("@babel/core");
+
+  _core = function () {
+    return data;
+  };
+
+  return data;
+}
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+const buildDefaultParam = (0, _core().template)(`
+  let VARIABLE_NAME =
+    arguments.length > ARGUMENT_KEY && arguments[ARGUMENT_KEY] !== undefined ?
+      arguments[ARGUMENT_KEY]
+    :
+      DEFAULT_VALUE;
+`);
+const buildLooseDefaultParam = (0, _core().template)(`
+  if (ASSIGNMENT_IDENTIFIER === UNDEFINED) {
+    ASSIGNMENT_IDENTIFIER = DEFAULT_VALUE;
+  }
+`);
+const buildLooseDestructuredDefaultParam = (0, _core().template)(`
+  let ASSIGNMENT_IDENTIFIER = PARAMETER_NAME === UNDEFINED ? DEFAULT_VALUE : PARAMETER_NAME ;
+`);
+const buildSafeArgumentsAccess = (0, _core().template)(`
+  let $0 = arguments.length > $1 ? arguments[$1] : undefined;
+`);
+
+function isSafeBinding(scope, node) {
+  if (!scope.hasOwnBinding(node.name)) return true;
+  const {
+    kind
+  } = scope.getOwnBinding(node.name);
+  return kind === "param" || kind === "local";
+}
+
+const iifeVisitor = {
+  ReferencedIdentifier(path, state) {
+    const {
+      scope,
+      node
+    } = path;
+
+    if (node.name === "eval" || !isSafeBinding(scope, node)) {
+      state.iife = true;
+      path.stop();
+    }
+  },
+
+  Scope(path) {
+    path.skip();
+  }
+
+};
+
+function convertFunctionParams(path, loose) {
+  const {
+    node,
+    scope
+  } = path;
+  const state = {
+    iife: false,
+    scope: scope
+  };
+  const body = [];
+  const params = path.get("params");
+  let firstOptionalIndex = null;
+
+  for (let i = 0; i < params.length; i++) {
+    const param = params[i];
+    const paramIsAssignmentPattern = param.isAssignmentPattern();
+
+    if (paramIsAssignmentPattern && (loose || node.kind === "set")) {
+      const left = param.get("left");
+      const right = param.get("right");
+      const undefinedNode = scope.buildUndefinedNode();
+
+      if (left.isIdentifier()) {
+        body.push(buildLooseDefaultParam({
+          ASSIGNMENT_IDENTIFIER: _core().types.cloneNode(left.node),
+          DEFAULT_VALUE: right.node,
+          UNDEFINED: undefinedNode
+        }));
+        param.replaceWith(left.node);
+      } else if (left.isObjectPattern() || left.isArrayPattern()) {
+        const paramName = scope.generateUidIdentifier();
+        body.push(buildLooseDestructuredDefaultParam({
+          ASSIGNMENT_IDENTIFIER: left.node,
+          DEFAULT_VALUE: right.node,
+          PARAMETER_NAME: _core().types.cloneNode(paramName),
+          UNDEFINED: undefinedNode
+        }));
+        param.replaceWith(paramName);
+      }
+    } else if (paramIsAssignmentPattern) {
+      if (firstOptionalIndex === null) firstOptionalIndex = i;
+      const left = param.get("left");
+      const right = param.get("right");
+
+      if (!state.iife) {
+        if (right.isIdentifier() && !isSafeBinding(scope, right.node)) {
+          state.iife = true;
+        } else {
+          right.traverse(iifeVisitor, state);
+        }
+      }
+
+      const defNode = buildDefaultParam({
+        VARIABLE_NAME: left.node,
+        DEFAULT_VALUE: right.node,
+        ARGUMENT_KEY: _core().types.numericLiteral(i)
+      });
+      body.push(defNode);
+    } else if (firstOptionalIndex !== null) {
+      const defNode = buildSafeArgumentsAccess([param.node, _core().types.numericLiteral(i)]);
+      body.push(defNode);
+    } else if (param.isObjectPattern() || param.isArrayPattern()) {
+      const uid = path.scope.generateUidIdentifier("ref");
+
+      const defNode = _core().types.variableDeclaration("let", [_core().types.variableDeclarator(param.node, uid)]);
+
+      body.push(defNode);
+      param.replaceWith(_core().types.cloneNode(uid));
+    }
+
+    if (!state.iife && !param.isIdentifier()) {
+      param.traverse(iifeVisitor, state);
+    }
+  }
+
+  if (body.length === 0) return false;
+
+  if (firstOptionalIndex !== null) {
+    node.params = node.params.slice(0, firstOptionalIndex);
+  }
+
+  path.ensureBlock();
+
+  if (state.iife) {
+    body.push((0, _helperCallDelegate().default)(path, scope));
+    path.set("body", _core().types.blockStatement(body));
+  } else {
+    path.get("body").unshiftContainer("body", body);
+  }
+
+  return true;
+}