add new rule

scripts/tslint/noIncrementDecrementRule.ts

@@ -0,0 +1,35 @@
+import * as Lint from "tslint/lib/lint";
+import * as ts from "typescript";
+
+
+export class Rule extends Lint.Rules.AbstractRule {
+    public static FAILURE_STRING = "Don't use '++' or '--' operators outside for for loops or statements - prefer '+= 1' and '-= 1'.";
+
+    public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
+        return this.applyWithWalker(new IncrementDecrementWalker(sourceFile, this.getOptions()));
+    }
+}
+
+class IncrementDecrementWalker extends Lint.RuleWalker {
+
+    visitPostfixUnaryExpression(node: ts.PostfixUnaryExpression) {
+        super.visitPostfixUnaryExpression(node);
+        if (node.operator === ts.SyntaxKind.PlusPlusToken || node.operator == ts.SyntaxKind.MinusMinusToken) {
+            this.visitIncrementDecrement(node);
+        }
+    }
+
+    visitPrefixUnaryExpression(node: ts.PrefixUnaryExpression) {
+        super.visitPrefixUnaryExpression(node);
+        if (node.operator === ts.SyntaxKind.PlusPlusToken || node.operator == ts.SyntaxKind.MinusMinusToken) {
+            this.visitIncrementDecrement(node);
+        }
+    }
+
+    visitIncrementDecrement(node: ts.UnaryExpression) {
+        if (node.parent && (node.parent.kind === ts.SyntaxKind.ExpressionStatement || node.parent.kind === ts.SyntaxKind.ForStatement)) {
+            return;
+        }
+        this.addFailure(this.createFailure(node.getStart(), node.getWidth(), Rule.FAILURE_STRING));
+    }
+}