Files
babel/src/babel/traversal/path/index.js
Sebastian McKenzie fce2aa8fa3 add support for esquery
2015-05-05 03:21:31 +01:00

1091 lines
25 KiB
JavaScript

import PathHoister from "./hoister";
import * as virtualTypes from "./virtual-types";
import isBoolean from "lodash/lang/isBoolean";
import isNumber from "lodash/lang/isNumber";
import isRegExp from "lodash/lang/isRegExp";
import isString from "lodash/lang/isString";
import codeFrame from "../../helpers/code-frame";
import parse from "../../helpers/parse";
import { explode } from "../visitors";
import traverse from "../index";
import includes from "lodash/collection/includes";
import assign from "lodash/object/assign";
import extend from "lodash/object/extend";
import Scope from "../scope";
import * as t from "../../types";
var hoistVariablesVisitor = explode({
Function() {
this.skip();
},
VariableDeclaration(node, parent, scope) {
if (node.kind !== "var") return;
var bindings = this.getBindingIdentifiers();
for (var key in bindings) {
scope.push({ id: bindings[key] });
}
var exprs = [];
for (var i = 0; i < node.declarations.length; i++) {
var declar = node.declarations[i];
if (declar.init) {
exprs.push(t.expressionStatement(
t.assignmentExpression("=", declar.id, declar.init)
));
}
}
return exprs;
}
});
export default class TraversalPath {
constructor(parent, container) {
this.container = container;
this.parent = parent;
this.data = {};
}
/**
* Description
*/
static get(parentPath: TraversalPath, context?: TraversalContext, parent, container, key, file?: File) {
var targetNode = container[key];
var paths = container._paths = container._paths || [];
var path;
for (var i = 0; i < paths.length; i++) {
var pathCheck = paths[i];
if (pathCheck.node === targetNode) {
path = pathCheck;
break;
}
}
if (!path) {
path = new TraversalPath(parent, container);
paths.push(path);
}
path.setContext(parentPath, context, key, file);
return path;
}
/**
* Description
*/
static getScope(path: TraversalPath, scope: Scope, file?: File) {
var ourScope = scope;
// we're entering a new scope so let's construct it!
if (path.isScope()) {
ourScope = new Scope(path, scope, file);
}
return ourScope;
}
/**
* Description
*/
getAncestry() {
var ancestry = [];
var path = this.parentPath;
while (path) {
ancestry.push(path.node);
path = path.parentPath;
}
return ancestry;
}
/**
* Description
*/
queueNode(path) {
if (this.context) {
this.context.queue.push(path);
}
}
/**
* Description
*/
insertBefore(nodes) {
nodes = this._verifyNodeList(nodes);
if (this.parentPath.isExpressionStatement() || this.parentPath.isLabeledStatement()) {
return this.parentPath.insertBefore(nodes);
} else if (this.isPreviousType("Expression") || (this.parentPath.isForStatement() && this.key === "init")) {
if (this.node) nodes.push(this.node);
this.replaceExpressionWithStatements(nodes);
} else if (this.isPreviousType("Statement") || !this.type) {
this._maybePopFromStatements(nodes);
if (Array.isArray(this.container)) {
this._containerInsertBefore(nodes);
} else if (this.isStatementOrBlock()) {
if (this.node) nodes.push(this.node);
this.container[this.key] = t.blockStatement(nodes);
this.checkSelf();
} else {
throw new Error("We don't know what to do with this node type. We were previously a Statement but we can't fit in here?");
}
} else {
throw new Error("No clue what to do with this node type.");
}
}
_containerInsert(from, nodes) {
this.updateSiblingKeys(from, nodes.length);
var paths = [];
for (var i = 0; i < nodes.length; i++) {
var to = from + i;
var node = nodes[i];
this.container.splice(to, 0, node);
if (this.context) {
var path = this.context.create(this.parent, this.container, to);
paths.push(path);
this.queueNode(path);
} else {
paths.push(TraversalPath.get(this, null, node, this.container, to));
}
}
this.checkPaths(paths);
}
_containerInsertBefore(nodes) {
this._containerInsert(this.key, nodes);
}
_containerInsertAfter(nodes) {
this._containerInsert(this.key + 1, nodes);
}
_maybePopFromStatements(nodes) {
var last = nodes[nodes.length - 1];
if (t.isExpressionStatement(last) && t.isIdentifier(last.expression) && !this.isCompletionRecord()) {
nodes.pop();
}
}
/**
* Description
*/
isCompletionRecord() {
var path = this;
do {
var container = path.container;
if (Array.isArray(container) && path.key !== container.length - 1) {
return false;
}
} while (path = path.parentPath && !path.isProgram());
return true;
}
/**
* Description
*/
isStatementOrBlock() {
if (t.isLabeledStatement(this.parent) || t.isBlockStatement(this.container)) {
return false;
} else {
return includes(t.STATEMENT_OR_BLOCK_KEYS, this.key);
}
}
/**
* Description
*/
insertAfter(nodes) {
nodes = this._verifyNodeList(nodes);
if (this.parentPath.isExpressionStatement() || this.parentPath.isLabeledStatement()) {
return this.parentPath.insertAfter(nodes);
} else if (this.isPreviousType("Expression") || (this.parentPath.isForStatement() && this.key === "init")) {
if (this.node) {
var temp = this.scope.generateTemp();
nodes.unshift(t.expressionStatement(t.assignmentExpression("=", temp, this.node)));
nodes.push(t.expressionStatement(temp));
}
this.replaceExpressionWithStatements(nodes);
} else if (this.isPreviousType("Statement") || !this.type) {
this._maybePopFromStatements(nodes);
if (Array.isArray(this.container)) {
this._containerInsertAfter(nodes);
} else if (this.isStatementOrBlock()) {
if (this.node) nodes.unshift(this.node);
this.container[this.key] = t.blockStatement(nodes);
this.checkSelf();
} else {
throw new Error("We don't know what to do with this node type. We were previously a Statement but we can't fit in here?");
}
} else {
throw new Error("No clue what to do with this node type.");
}
}
/**
* Description
*/
updateSiblingKeys(fromIndex, incrementBy) {
var paths = this.container._paths;
for (var i = 0; i < paths.length; i++) {
let path = paths[i];
if (path.key >= fromIndex) {
path.key += incrementBy;
}
}
}
/**
* Description
*/
setData(key, val) {
return this.data[key] = val;
}
/**
* Description
*/
getData(key, def) {
var val = this.data[key];
if (!val && def) val = this.data[key] = def;
return val;
}
/**
* Description
*/
setScope(file?) {
var target = this.context || this.parentPath;
this.scope = TraversalPath.getScope(this, target && target.scope, file);
}
/**
* Description
*/
clearContext() {
this.context = null;
}
/**
* Description
*/
setContext(parentPath, context, key, file?) {
this.shouldSkip = false;
this.shouldStop = false;
this.removed = false;
this.parentPath = parentPath || this.parentPath;
this.key = key;
if (context) {
this.context = context;
this.state = context.state;
this.opts = context.opts;
}
this.type = this.node && this.node.type;
var log = file && this.type === "Program";
if (log) file.log.debug("Start scope building");
this.setScope(file);
if (log) file.log.debug("End scope building");
}
_remove() {
if (Array.isArray(this.container)) {
this.container.splice(this.key, 1);
this.updateSiblingKeys(this.key, -1);
} else {
this.container[this.key] = null;
}
}
/**
* Description
*/
remove() {
this._remove();
this.removed = true;
var parentPath = this.parentPath;
var parent = this.parent;
if (!parentPath) return;
// we've just removed the last declarator of a variable declaration so there's no point in
// keeping it
if (parentPath.isVariableDeclaration() && parent.declarations.length === 0) {
return parentPath.remove();
}
// we're the child of an expression statement so we should remove the parent
if (parentPath.isExpressionStatement()) {
return parentPath.remove();
}
// we've just removed the second element of a sequence expression so let's turn that sequence
// expression into a regular expression
if (parentPath.isSequenceExpression() && parent.expressions.length === 1) {
parentPath.replaceWith(parent.expressions[0]);
}
// we're in a binary expression, better remove it and replace it with the last expression
if (parentPath.isBinary()) {
if (this.key === "left") {
parentPath.replaceWith(parent.right);
} else { // key === "right"
parentPath.replaceWith(parent.left);
}
}
}
/**
* Description
*/
skip() {
this.shouldSkip = true;
}
/**
* Description
*/
stop() {
this.shouldStop = true;
this.shouldSkip = true;
}
/**
* Description
*/
errorWithNode(msg, Error = SyntaxError) {
var loc = this.node.loc.start;
var err = new Error(`Line ${loc.line}: ${msg}`);
err.loc = loc;
return err;
}
get node() {
if (this.removed) {
return null;
} else {
return this.container[this.key];
}
}
set node(replacement) {
throw new Error("Don't use `path.node = newNode;`, use `path.replaceWith(newNode)` or `path.replaceWithMultiple([newNode])`");
}
/**
* Description
*/
replaceInline(nodes) {
if (Array.isArray(nodes)) {
if (Array.isArray(this.container)) {
nodes = this._verifyNodeList(nodes);
this._containerInsertAfter(nodes);
return this.remove();
} else {
return this.replaceWithMultiple(nodes);
}
} else {
return this.replaceWith(nodes);
}
}
/**
* Description
*/
_verifyNodeList(nodes) {
if (nodes.constructor !== Array) {
nodes = [nodes];
}
for (var i = 0; i < nodes.length; i++) {
var node = nodes[i];
if (!node) {
throw new Error(`Node list has falsy node with the index of ${i}`);
} else if (typeof node !== "object") {
throw new Error(`Node list contains a non-object node with the index of ${i}`);
} else if (!node.type) {
throw new Error(`Node list contains a node without a type with the index of ${i}`);
}
}
return nodes;
}
/**
* Description
*/
unshiftContainer(containerKey, nodes) {
nodes = this._verifyNodeList(nodes);
// get the first path and insert our nodes before it, if it doesn't exist then it
// doesn't matter, our nodes will be inserted anyway
var container = this.node[containerKey];
var path = TraversalPath.get(this, null, this.node, container, 0);
return path.insertBefore(nodes);
}
/**
* Description
*/
pushContainer(containerKey, nodes) {
nodes = this._verifyNodeList(nodes);
// get an invisible path that represents the last node + 1 and replace it with our
// nodes, effectively inlining it
var container = this.node[containerKey];
var i = container.length;
var path = TraversalPath.get(this, null, this.node, container, i);
return path.replaceWith(nodes, true);
}
/**
* Description
*/
replaceWithMultiple(nodes: Array<Object>) {
nodes = this._verifyNodeList(nodes);
t.inheritsComments(nodes[0], this.node);
this.container[this.key] = null;
this.insertAfter(nodes);
if (!this.node) this.remove();
}
/**
* Description
*/
replaceWithSourceString(replacement) {
try {
replacement = `(${replacement})`;
replacement = parse(replacement);
} catch (err) {
var loc = err.loc;
if (loc) {
err.message += " - make sure this is an expression.";
err.message += "\n" + codeFrame(replacement, loc.line, loc.column + 1);
}
throw err;
}
replacement = replacement.program.body[0].expression;
traverse.removeProperties(replacement);
return this.replaceWith(replacement);
}
/**
* Description
*/
replaceWith(replacement, whateverAllowed) {
if (this.removed) {
throw new Error("You can't replace this node, we've already removed it");
}
if (!replacement) {
throw new Error("You passed `path.replaceWith()` a falsy node, use `path.remove()` instead");
}
if (this.node === replacement) {
return this.checkSelf();
}
// normalise inserting an entire AST
if (t.isProgram(replacement)) {
replacement = replacement.body;
whateverAllowed = true;
}
if (Array.isArray(replacement)) {
if (whateverAllowed) {
return this.replaceWithMultiple(replacement);
} else {
throw new Error("Don't use `path.replaceWith()` with an array of nodes, use `path.replaceWithMultiple()`");
}
}
if (typeof replacement === "string") {
if (whateverAllowed) {
return this.replaceWithSourceString(replacement);
} else {
throw new Error("Don't use `path.replaceWith()` with a string, use `path.replaceWithSourceString()`");
}
}
// replacing a statement with an expression so wrap it in an expression statement
if (this.isPreviousType("Statement") && t.isExpression(replacement)) {
replacement = t.expressionStatement(replacement);
}
// replacing an expression with a statement so let's explode it
if (this.isPreviousType("Expression") && t.isStatement(replacement)) {
return this.replaceExpressionWithStatements([replacement]);
}
var oldNode = this.node;
if (oldNode) t.inheritsComments(replacement, oldNode);
// replace the node
this.container[this.key] = replacement;
this.type = replacement.type;
// potentially create new scope
this.setScope();
this.checkSelf();
}
/**
* Description
*/
checkSelf() {
this.checkPaths(this);
}
/**
* Description
*/
checkPaths(paths) {
var scope = this.scope;
var file = scope && scope.file;
if (file) file.checkPath(paths);
}
/**
* Description
*/
getStatementParent(): ?TraversalPath {
var path = this;
do {
if (!path.parentPath || (Array.isArray(path.container) && path.isStatement())) {
break;
} else {
path = path.parentPath;
}
} while (path);
if (path && (path.isProgram() || path.isFile())) {
throw new Error("File/Program node, we can't possibly find a statement parent to this");
}
return path;
}
/**
* Description
*/
getLastStatements(): Array<TraversalPath> {
var paths = [];
var add = function (path) {
if (path) paths = paths.concat(path.getLastStatements());
};
if (this.isIfStatement()) {
add(this.get("consequent"));
add(this.get("alternate"));
} else if (this.isDoExpression()) {
add(this.get("body"));
} else if (this.isProgram() || this.isBlockStatement()) {
add(this.get("body").pop());
} else {
paths.push(this);
}
return paths;
}
/**
* Description
*/
replaceExpressionWithStatements(nodes: Array) {
var toSequenceExpression = t.toSequenceExpression(nodes, this.scope);
if (toSequenceExpression) {
return this.replaceWith(toSequenceExpression);
} else {
var container = t.functionExpression(null, [], t.blockStatement(nodes));
container.shadow = true;
// add implicit returns to all ending expression statements
var last = this.getLastStatements();
for (var i = 0; i < last.length; i++) {
var lastNode = last[i];
if (lastNode.isExpressionStatement()) {
lastNode.replaceWith(t.returnStatement(lastNode.node.expression));
}
}
this.replaceWith(t.callExpression(container, []));
this.traverse(hoistVariablesVisitor);
return this.node;
}
}
/**
* Description
*/
call(key) {
var node = this.node;
if (!node) return;
var opts = this.opts;
var fns = [].concat(opts[key]);
if (opts[node.type]) {
fns = fns.concat(opts[node.type][key]);
}
for (var fn of (fns: Array)) {
if (!fn) continue;
// call the function with the params (node, parent, scope, state)
var replacement = fn.call(this, node, this.parent, this.scope, this.state);
if (replacement) this.replaceWith(replacement, true);
if (this.shouldStop) break;
}
}
/**
* Description
*/
isBlacklisted(): boolean {
var blacklist = this.opts.blacklist;
return blacklist && blacklist.indexOf(this.node.type) > -1;
}
/**
* Description
*/
visit(): boolean {
if (this.isBlacklisted()) return false;
if (this.opts.shouldSkip(this)) return false;
this.call("enter");
if (this.shouldSkip) {
return this.shouldStop;
}
var node = this.node;
var opts = this.opts;
if (node) {
if (Array.isArray(node)) {
// traverse over these replacement nodes we purposely don't call exitNode
// as the original node has been destroyed
for (var i = 0; i < node.length; i++) {
traverse.node(node[i], opts, this.scope, this.state, this);
}
} else {
traverse.node(node, opts, this.scope, this.state, this);
this.call("exit");
}
}
return this.shouldStop;
}
/**
* Description
*/
getSibling(key) {
return TraversalPath.get(this.parentPath, null, this.parent, this.container, key, this.file);
}
/**
* Description
*/
get(key: string): TraversalPath {
var parts = key.split(".");
if (parts.length === 1) { // "foo"
return this._getKey(key);
} else { // "foo.bar"
return this._getPattern(parts);
}
}
/**
* Description
*/
_getKey(key) {
var node = this.node;
var container = node[key];
if (Array.isArray(container)) {
// requested a container so give them all the paths
return container.map((_, i) => {
return TraversalPath.get(this, null, node, container, i);
});
} else {
return TraversalPath.get(this, null, node, node, key);
}
}
/**
* Description
*/
_getPattern(parts) {
var path = this;
for (var i = 0; i > parts.length; i++) {
var part = parts[i];
if (part === ".") {
path = path.parentPath;
} else {
if (Array.isArray(path)) {
path = path[part];
} else {
path = path.get(part);
}
}
}
return path;
}
/**
* Description
*/
has(key): boolean {
var val = this.node[key];
if (val && Array.isArray(val)) {
return !!val.length;
} else {
return !!val;
}
}
/**
* Description
*/
is(key): boolean {
return this.has(key);
}
/**
* Description
*/
isnt(key): boolean {
return !this.has(key);
}
/**
* Description
*/
getTypeAnnotation(): {
inferred: boolean;
annotation: ?Object;
} {
if (this.typeInfo) {
return this.typeInfo;
}
var info = this.typeInfo = {
inferred: false,
annotation: null
};
var type = this.node.typeAnnotation;
if (!type) {
info.inferred = true;
type = this.inferType(this);
}
if (type) {
if (t.isTypeAnnotation(type)) type = type.typeAnnotation;
info.annotation = type;
}
return info;
}
/**
* Description
*/
resolve(): ?TraversalPath {
if (this.isVariableDeclarator()) {
if (this.get("id").isIdentifier()) {
return this.get("init").resolve();
} else {
// otherwise it's a request for a destructuring declarator and i'm not
// ready to resolve those just yet
}
} else if (this.isIdentifier()) {
var binding = this.scope.getBinding(this.node.name);
if (!binding || !binding.constant) return;
// todo: take into consideration infinite recursion #1149
return;
if (binding.path === this) {
return this;
} else {
return binding.path.resolve();
}
} else if (this.isMemberExpression()) {
// this is dangerous, as non-direct target assignments will mutate it's state
// making this resolution inaccurate
var targetKey = this.toComputedKey();
if (!t.isLiteral(targetKey)) return;
var targetName = targetKey.value;
var target = this.get("object").resolve();
if (!target || !target.isObjectExpression()) return;
var props = target.get("properties");
for (var i = 0; i < props.length; i++) {
var prop = props[i];
if (!prop.isProperty()) continue;
var key = prop.get("key");
// { foo: obj }
var match = prop.isnt("computed") && key.isIdentifier({ name: targetName });
// { "foo": "obj" } or { ["foo"]: "obj" }
match = match || key.isLiteral({ value: targetName });
if (match) return prop.get("value");
}
} else {
return this;
}
}
/**
* Description
*/
inferType(path: TraversalPath): ?Object {
path = path.resolve();
if (!path) return;
if (path.isRestElement() || path.parentPath.isRestElement() || path.isArrayExpression()) {
return t.genericTypeAnnotation(t.identifier("Array"));
}
if (path.parentPath.isTypeCastExpression()) {
return path.parentPath.node.typeAnnotation;
}
if (path.isTypeCastExpression()) {
return path.node.typeAnnotation;
}
if (path.isObjectExpression()) {
return t.genericTypeAnnotation(t.identifier("Object"));
}
if (path.isFunction()) {
return t.identifier("Function");
}
if (path.isLiteral()) {
var value = path.node.value;
if (isString(value)) return t.stringTypeAnnotation();
if (isNumber(value)) return t.numberTypeAnnotation();
if (isBoolean(value)) return t.booleanTypeAnnotation();
}
if (path.isCallExpression()) {
var callee = path.get("callee").resolve();
if (callee && callee.isFunction()) return callee.node.returnType;
}
}
/**
* Description
*/
isPreviousType(type: string): boolean {
return t.isType(this.type, type);
}
/**
* Description
*/
isTypeGeneric(genericName: string, opts = {}): boolean {
var typeInfo = this.getTypeAnnotation();
var type = typeInfo.annotation;
if (!type) return false;
if (type.inferred && opts.inference === false) {
return false;
}
if (!t.isGenericTypeAnnotation(type) || !t.isIdentifier(type.id, { name: genericName })) {
return false;
}
if (opts.requireTypeParameters && !type.typeParameters) {
return false;
}
return true;
}
/**
* Description
*/
getBindingIdentifiers() {
return t.getBindingIdentifiers(this.node);
}
/**
* Description
*/
traverse(visitor, state) {
traverse(this.node, visitor, this.scope, state, this);
}
/**
* Description
*/
hoist(scope = this.scope) {
var hoister = new PathHoister(this, scope);
return hoister.run();
}
/**
* Match the current node if it matches the provided `pattern`.
*
* For example, given the match `React.createClass` it would match the
* parsed nodes of `React.createClass` and `React["createClass"]`.
*/
matchesPattern(pattern: string, allowPartial?: boolean): boolean {
var parts = pattern.split(".");
// not a member expression
if (!this.isMemberExpression()) return false;
var search = [this.node];
var i = 0;
function matches(name) {
var part = parts[i];
return part === "*" || name === part;
}
while (search.length) {
var node = search.shift();
if (allowPartial && i === parts.length) {
return true;
}
if (t.isIdentifier(node)) {
// this part doesn't match
if (!matches(node.name)) return false;
} else if (t.isLiteral(node)) {
// this part doesn't match
if (!matches(node.value)) return false;
} else if (t.isMemberExpression(node)) {
if (node.computed && !t.isLiteral(node.property)) {
// we can't deal with this
return false;
} else {
search.push(node.object);
search.push(node.property);
continue;
}
} else {
// we can't deal with this
return false;
}
// too many parts
if (++i > parts.length) {
return false;
}
}
return true;
}
}
assign(TraversalPath.prototype, require("./evaluation"));
assign(TraversalPath.prototype, require("./conversion"));
for (let type in virtualTypes) {
if (type[0] === "_") continue;
TraversalPath.prototype[`is${type}`] = function (opts) {
return virtualTypes[type].checkPath(this, opts);
};
}
for (let type of (t.TYPES: Array)) {
let typeKey = `is${type}`;
TraversalPath.prototype[typeKey] = function (opts) {
return t[typeKey](this.node, opts);
};
}