DevTools: Consolidate completion code into JavaScriptAutocomplete.js

third_party/WebKit/Source/devtools/front_end/components/JavaScriptAutocomplete.js

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+WebInspector.JavaScriptAutocomplete = {};
+
+/**
+ * @param {!Element} proxyElement
+ * @param {!Range} wordRange
+ * @param {boolean} force
+ * @param {function(!Array.<string>, number=)} completionsReadyCallback
+ */
+WebInspector.JavaScriptAutocomplete.completionsForTextPromptInCurrentContext = function(proxyElement, wordRange, force, completionsReadyCallback)
+{
+    var expressionRange = wordRange.cloneRange();
+    expressionRange.collapse(true);
+    expressionRange.setStartBefore(proxyElement);
+    WebInspector.JavaScriptAutocomplete.completionsForTextInCurrentContext(expressionRange.toString(), wordRange.toString(), force).then(completionsReadyCallback);
+};
+
+/**
+ * @param {string} text
+ * @param {string} completionsPrefix
+ * @param {boolean=} force
+ * @return {!Promise<!Array<string>>}
+ */
+WebInspector.JavaScriptAutocomplete.completionsForTextInCurrentContext = function(text, completionsPrefix, force)
+{
+    var index;
+    var stopChars = new Set(" =:({;,!+-*/&|^<>`".split(""));
+    for (index = text.length - 1; index >= 0; index--) {
+        // Pass less stop characters to rangeOfWord so the range will be a more complete expression.
+        if (stopChars.has(text.charAt(index)))
+            break;
+    }
+    var clippedExpression = text.substring(index + 1);
+    var bracketCount = 0;
+
+    index = clippedExpression.length - 1;
+    while (index >= 0) {
+        var character = clippedExpression.charAt(index);
+        if (character === "]")
+            bracketCount++;
+        // Allow an open bracket at the end for property completion.
+        if (character === "[" && index < clippedExpression.length - 1) {
+            bracketCount--;
+            if (bracketCount < 0)
+                break;
+        }
+        index--;
+    }
+    clippedExpression = clippedExpression.substring(index + 1);
+
+    return WebInspector.JavaScriptAutocomplete.completionsForExpression(clippedExpression, completionsPrefix, force);
+};
+
+
+/**
+ * @param {string} expressionString
+ * @param {string} prefix
+ * @param {boolean=} force
+ * @return {!Promise<!Array<string>>}
+ */
+WebInspector.JavaScriptAutocomplete.completionsForExpression = function(expressionString, prefix, force)
+{
+    var executionContext = WebInspector.context.flavor(WebInspector.ExecutionContext);
+    if (!executionContext)
+        return Promise.resolve([]);
+
+    var lastIndex = expressionString.length - 1;
+
+    var dotNotation = (expressionString[lastIndex] === ".");
+    var bracketNotation = (expressionString[lastIndex] === "[");
+
+    if (dotNotation || bracketNotation)
+        expressionString = expressionString.substr(0, lastIndex);
+
+    // User is entering float value, do not suggest anything.
+    if (expressionString && !isNaN(expressionString))
+        return Promise.resolve([]);
+
+    if (!prefix && !expressionString && !force)
+        return Promise.resolve([]);
+
+    var fulfill;
+    var promise = new Promise(x => fulfill = x);
+
+    if (!expressionString && executionContext.debuggerModel.selectedCallFrame())
+        executionContext.debuggerModel.selectedCallFrame().variableNames(receivedPropertyNames);
+    else
+        executionContext.evaluate(expressionString, "completion", true, true, false, false, false, evaluated);
+
+    return promise;
+    /**
+     * @param {?WebInspector.RemoteObject} result
+     * @param {!RuntimeAgent.ExceptionDetails=} exceptionDetails
+     */
+    function evaluated(result, exceptionDetails)
+    {
+        if (!result || !!exceptionDetails) {
+            fulfill([]);
+            return;
+        }
+
+        /**
+         * @param {?WebInspector.RemoteObject} object
+         * @return {!Promise<?WebInspector.RemoteObject>}
+         */
+        function extractTarget(object)
+        {
+            if (!object)
+                return Promise.resolve(/** @type {?WebInspector.RemoteObject} */(null));
+            if (object.type !== "object" || object.subtype !== "proxy")
+                return Promise.resolve(/** @type {?WebInspector.RemoteObject} */(object));
+            return object.getOwnPropertiesPromise().then(extractTargetFromProperties).then(extractTarget);
+        }
+
+        /**
+         * @param {!{properties: ?Array<!WebInspector.RemoteObjectProperty>, internalProperties: ?Array<!WebInspector.RemoteObjectProperty>}} properties
+         * @return {?WebInspector.RemoteObject}
+         */
+        function extractTargetFromProperties(properties)
+        {
+            var internalProperties = properties.internalProperties || [];
+            var target = internalProperties.find(property => property.name === "[[Target]]");
+            return target ? target.value : null;
+        }
+
+        /**
+         * @param {string=} type
+         * @return {!Object}
+         * @suppressReceiverCheck
+         * @this {Object}
+         */
+        function getCompletions(type)
+        {
+            var object;
+            if (type === "string")
+                object = new String("");
+            else if (type === "number")
+                object = new Number(0);
+            else if (type === "boolean")
+                object = new Boolean(false);
+            else
+                object = this;
+
+            var resultSet = { __proto__: null };
+            try {
+                for (var o = object; o; o = Object.getPrototypeOf(o)) {
+                    if ((type === "array" || type === "typedarray") && o === object && ArrayBuffer.isView(o) && o.length > 9999)
+                        continue;
+                    var names = Object.getOwnPropertyNames(o);
+                    var isArray = Array.isArray(o);
+                    for (var i = 0; i < names.length; ++i) {
+                        // Skip array elements indexes.
+                        if (isArray && /^[0-9]/.test(names[i]))
+                            continue;
+                        resultSet[names[i]] = true;
+                    }
+                }
+            } catch (e) {
+            }
+            return resultSet;
+        }
+
+        /**
+         * @param {?WebInspector.RemoteObject} object
+         */
+        function completionsForObject(object)
+        {
+            if (!object)
+                receivedPropertyNames(null);
+            else if (object.type === "object" || object.type === "function")
+                object.callFunctionJSON(getCompletions, [WebInspector.RemoteObject.toCallArgument(object.subtype)], receivedPropertyNames);
+            else if (object.type === "string" || object.type === "number" || object.type === "boolean")
+                executionContext.evaluate("(" + getCompletions + ")(\"" + result.type + "\")", "completion", false, true, true, false, false, receivedPropertyNamesFromEval);
+        }
+
+        extractTarget(result).then(completionsForObject);
+    }
+
+    /**
+     * @param {?WebInspector.RemoteObject} result
+     * @param {!RuntimeAgent.ExceptionDetails=} exceptionDetails
+     */
+    function receivedPropertyNamesFromEval(result, exceptionDetails)
+    {
+        executionContext.target().runtimeAgent().releaseObjectGroup("completion");
+        if (result && !exceptionDetails)
+            receivedPropertyNames(/** @type {!Object} */(result.value));
+        else
+            fulfill([]);
+    }
+
+    /**
+     * @param {?Object} propertyNames
+     */
+    function receivedPropertyNames(propertyNames)
+    {
+        executionContext.target().runtimeAgent().releaseObjectGroup("completion");
+        if (!propertyNames) {
+            fulfill([]);
+            return;
+        }
+        var includeCommandLineAPI = (!dotNotation && !bracketNotation);
+        if (includeCommandLineAPI) {
+            const commandLineAPI = ["dir", "dirxml", "keys", "values", "profile", "profileEnd", "monitorEvents", "unmonitorEvents", "inspect", "copy", "clear",
+                "getEventListeners", "debug", "undebug", "monitor", "unmonitor", "table", "$", "$$", "$x"];
+            for (var i = 0; i < commandLineAPI.length; ++i)
+                propertyNames[commandLineAPI[i]] = true;
+        }
+        fulfill(WebInspector.JavaScriptAutocomplete._completionsForPrefix(dotNotation, bracketNotation, expressionString, prefix, Object.keys(propertyNames)));
+    }
+};
+
+/**
+ * @param {boolean} dotNotation
+ * @param {boolean} bracketNotation
+ * @param {string} expressionString
+ * @param {string} prefix
+ * @param {!Array.<string>} properties
+ * @return {!Array<string>}
+ */
+WebInspector.JavaScriptAutocomplete._completionsForPrefix = function(dotNotation, bracketNotation, expressionString, prefix, properties) {
+    if (bracketNotation) {
+        if (prefix.length && prefix[0] === "'")
+            var quoteUsed = "'";
+        else
+            var quoteUsed = "\"";
+    }
+
+    var results = [];
+
+    if (!expressionString) {
+        const keywords = ["break", "case", "catch", "continue", "default", "delete", "do", "else", "finally", "for", "function", "if", "in",
+                            "instanceof", "new", "return", "switch", "this", "throw", "try", "typeof", "var", "void", "while", "with"];
+        properties = properties.concat(keywords);
+    }
+
+    properties.sort();
+
+    for (var i = 0; i < properties.length; ++i) {
+        var property = properties[i];
+
+        // Assume that all non-ASCII characters are letters and thus can be used as part of identifier.
+        if (dotNotation && !/^[a-zA-Z_$\u008F-\uFFFF][a-zA-Z0-9_$\u008F-\uFFFF]*$/.test(property))
+            continue;
+
+        if (bracketNotation) {
+            if (!/^[0-9]+$/.test(property))
+                property = quoteUsed + property.escapeCharacters(quoteUsed + "\\") + quoteUsed;
+            property += "]";
+        }
+
+        if (property.length < prefix.length)
+            continue;
+        if (prefix.length && !property.startsWith(prefix))
+            continue;
+
+        // Substitute actual newlines with newline characters. @see crbug.com/498421
+        results.push(property.split("\n").join("\\n"));
+    }
+    return results;
+};