no-magic-numbers rule ignores arguments in Number prototype methods

src/rules/noMagicNumbersRule.ts

@@ -17,10 +17,12 @@
 
 import * as ts from "typescript";
 
-import { isCallExpression, isIdentifier } from "tsutils";
+import { isCallExpression, isIdentifier, isPropertyAccessExpression } from "tsutils";
 import * as Lint from "../index";
 import { isNegativeNumberLiteral } from "../language/utils";
 
+const NUMBER_METHODS = ["toExponential", "toFixed", "toPrecision", "toString"];
+
 export class Rule extends Lint.Rules.AbstractRule {
     /* tslint:disable:object-literal-sort-keys */
     public static metadata: Lint.IRuleMetadata = {
@@ -61,7 +63,7 @@ export class Rule extends Lint.Rules.AbstractRule {
         ts.SyntaxKind.Parameter,
     ]);
 
-    public static DEFAULT_ALLOWED = [ -1, 0, 1 ];
+    public static DEFAULT_ALLOWED = [-1, 0, 1];
 
     public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
         return this.applyWithWalker(
@@ -77,8 +79,14 @@ export class Rule extends Lint.Rules.AbstractRule {
 class NoMagicNumbersWalker extends Lint.AbstractWalker<number[]> {
     public walk(sourceFile: ts.SourceFile) {
         const cb = (node: ts.Node): void => {
-            if (isCallExpression(node) && isIdentifier(node.expression) && node.expression.text === "parseInt") {
-                return node.arguments.length === 0 ? undefined : cb(node.arguments[0]);
+            if (isCallExpression(node)) {
+                if (isIdentifier(node.expression) && node.expression.text === "parseInt") {
+                    return node.arguments.length === 0 ? undefined : cb(node.arguments[0]);
+                }
+
+                if (isPropertyAccessExpression(node.expression) && NUMBER_METHODS.indexOf(node.expression.name.text) >= 0) {
+                    return;
+                }
             }
 
             if (node.kind === ts.SyntaxKind.NumericLiteral) {

test/rules/no-magic-numbers/default/test.ts.lint

@@ -30,3 +30,19 @@ class A {
 enum Test {
     key = 1337,
 }
+
+const a = 0.1234567801234567890;
+a.toFixed(2);
+a.toFixed(5);
+a.toFixed(10);
+
+a.toString(10);
+a.toString(36);
+
+a.toPrecision(3)
+a.toPrecision(10)
+a.toPrecision(20)
+
+const b = 77.1234;
+b.toExponential(4);
+b.toExponential(2);