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authorFlorian Dold <florian.dold@gmail.com>2017-05-28 00:38:50 +0200
committerFlorian Dold <florian.dold@gmail.com>2017-05-28 00:40:43 +0200
commit7fff4499fd915bcea3fa93b1aa8b35f4fe7a6027 (patch)
tree6de9a1aebd150a23b7f8c273ec657a5d0a18fe3e /node_modules/tslint/lib/rules/preferConditionalExpressionRule.js
parent963b7a41feb29cc4be090a2446bdfe0c1f1bcd81 (diff)
add linting (and some initial fixes)
Diffstat (limited to 'node_modules/tslint/lib/rules/preferConditionalExpressionRule.js')
-rw-r--r--node_modules/tslint/lib/rules/preferConditionalExpressionRule.js96
1 files changed, 96 insertions, 0 deletions
diff --git a/node_modules/tslint/lib/rules/preferConditionalExpressionRule.js b/node_modules/tslint/lib/rules/preferConditionalExpressionRule.js
new file mode 100644
index 000000000..7be4cbcbe
--- /dev/null
+++ b/node_modules/tslint/lib/rules/preferConditionalExpressionRule.js
@@ -0,0 +1,96 @@
+"use strict";
+/**
+ * @license
+ * Copyright 2017 Palantir Technologies, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+Object.defineProperty(exports, "__esModule", { value: true });
+var tslib_1 = require("tslib");
+var tsutils_1 = require("tsutils");
+var ts = require("typescript");
+var Lint = require("../index");
+var Rule = (function (_super) {
+ tslib_1.__extends(Rule, _super);
+ function Rule() {
+ return _super !== null && _super.apply(this, arguments) || this;
+ }
+ /* tslint:enable:object-literal-sort-keys */
+ Rule.FAILURE_STRING = function (assigned) {
+ return "Use a conditional expression instead of assigning to '" + assigned + "' in multiple places.";
+ };
+ Rule.prototype.apply = function (sourceFile) {
+ return this.applyWithFunction(sourceFile, walk);
+ };
+ return Rule;
+}(Lint.Rules.AbstractRule));
+/* tslint:disable:object-literal-sort-keys */
+Rule.metadata = {
+ ruleName: "prefer-conditional-expression",
+ description: (_a = ["\n Recommends to use a conditional expression instead of assigning to the same thing in each branch of an if statement."], _a.raw = ["\n Recommends to use a conditional expression instead of assigning to the same thing in each branch of an if statement."], Lint.Utils.dedent(_a)),
+ rationale: (_b = ["\n This reduces duplication and can eliminate an unnecessary variable declaration."], _b.raw = ["\n This reduces duplication and can eliminate an unnecessary variable declaration."], Lint.Utils.dedent(_b)),
+ optionsDescription: "Not configurable.",
+ options: null,
+ optionExamples: [true],
+ type: "functionality",
+ typescriptOnly: false,
+};
+exports.Rule = Rule;
+function walk(ctx) {
+ var sourceFile = ctx.sourceFile;
+ return ts.forEachChild(sourceFile, function cb(node) {
+ if (tsutils_1.isIfStatement(node)) {
+ var assigned = detect(node, sourceFile);
+ if (assigned !== undefined) {
+ ctx.addFailureAtNode(Lint.childOfKind(node, ts.SyntaxKind.IfKeyword), Rule.FAILURE_STRING(assigned.getText(sourceFile)));
+ // Be careful not to fail again for the "else if"
+ ts.forEachChild(node.expression, cb);
+ ts.forEachChild(node.thenStatement, cb);
+ if (node.elseStatement !== undefined) {
+ ts.forEachChild(node.elseStatement, cb);
+ }
+ return;
+ }
+ }
+ return ts.forEachChild(node, cb);
+ });
+}
+function detect(_a, sourceFile) {
+ var thenStatement = _a.thenStatement, elseStatement = _a.elseStatement;
+ if (elseStatement === undefined) {
+ return undefined;
+ }
+ var elze = tsutils_1.isIfStatement(elseStatement) ? detect(elseStatement, sourceFile) : getAssigned(elseStatement, sourceFile);
+ if (elze === undefined) {
+ return undefined;
+ }
+ var then = getAssigned(thenStatement, sourceFile);
+ return then !== undefined && nodeEquals(elze, then, sourceFile) ? then : undefined;
+}
+/** Returns the left side of an assignment. */
+function getAssigned(node, sourceFile) {
+ if (tsutils_1.isBlock(node)) {
+ return node.statements.length === 1 ? getAssigned(node.statements[0], sourceFile) : undefined;
+ }
+ else if (tsutils_1.isExpressionStatement(node) && tsutils_1.isBinaryExpression(node.expression)) {
+ var _a = node.expression, kind = _a.operatorToken.kind, left = _a.left, right = _a.right;
+ return kind === ts.SyntaxKind.EqualsToken && tsutils_1.isSameLine(sourceFile, right.getStart(sourceFile), right.end) ? left : undefined;
+ }
+ else {
+ return undefined;
+ }
+}
+function nodeEquals(a, b, sourceFile) {
+ return a.getText(sourceFile) === b.getText(sourceFile);
+}
+var _a, _b;