Add some missed underscores, update changelog and comments

packages/tslint-config/CHANGELOG.md

@@ -3,6 +3,7 @@
 v0.x.x - TBD
 ------------------------
     * Added custom 'underscore-privates' rule, requiring underscores to be prepended to private variable names
+    * Because our tools can be used in both a TS and JS environment, we want to make the private methods of any public facing interface show up at the bottom of auto-complete lists. Additionally, we wanted to remain consistent with respect to our usage of underscores in order to enforce this rule with a linter rule, rather then manual code reviews.
 
 v0.3.0 - _December 20, 2017_
 ------------------------

packages/tslint-config/rules/underscorePrivatesRule.ts

@@ -1,7 +1,7 @@
 import * as Lint from 'tslint';
 import * as ts from 'typescript';
 
-const UNDERSCORE = '_'.charCodeAt(0);
+const UNDERSCORE = '_';
 
 type RelevantClassMember =
     | ts.MethodDeclaration
@@ -9,15 +9,15 @@ type RelevantClassMember =
     | ts.GetAccessorDeclaration
     | ts.SetAccessorDeclaration;
 
-// Based on: https://github.com/DanielRosenwasser/underscore-privates-tslint-rule
+// Copied from: https://github.com/DanielRosenwasser/underscore-privates-tslint-rule
+// The version on github is not published on npm
 export class Rule extends Lint.Rules.AbstractRule {
-    public static FAILURE_STRING = 'private members name must be prefixed with an underscore';
+    public static FAILURE_STRING = 'private members must be prefixed with an underscore';
 
     public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
         return this.applyWithFunction(sourceFile, walk);
     }
 }
-
 function walk(ctx: Lint.WalkContext<void>): void {
     traverse(ctx.sourceFile);
 
@@ -26,23 +26,19 @@ function walk(ctx: Lint.WalkContext<void>): void {
         return ts.forEachChild(node, traverse);
     }
 }
-
 function checkNodeForViolations(ctx: Lint.WalkContext<void>, node: ts.Node): void {
     if (!isRelevantClassMember(node)) {
         return;
     }
-
     // The declaration might have a computed property name or a numeric name.
     const name = node.name;
     if (!nameIsIdentifier(name)) {
         return;
     }
-
     if (!nameStartsWithUnderscore(name.text) && memberIsPrivate(node)) {
         ctx.addFailureAtNode(name, Rule.FAILURE_STRING);
     }
 }
-
 function isRelevantClassMember(node: ts.Node): node is RelevantClassMember {
     switch (node.kind) {
         case ts.SyntaxKind.MethodDeclaration:
@@ -54,15 +50,12 @@ function isRelevantClassMember(node: ts.Node): node is RelevantClassMember {
             return false;
     }
 }
-
 function nameStartsWithUnderscore(text: string) {
-    return text.charCodeAt(0) === UNDERSCORE;
+    return text.charCodeAt(0) === UNDERSCORE.charCodeAt(0);
 }
-
 function memberIsPrivate(node: ts.Declaration) {
     return Lint.hasModifier(node.modifiers, ts.SyntaxKind.PrivateKeyword);
 }
-
 function nameIsIdentifier(node: ts.Node): node is ts.Identifier {
     return node.kind === ts.SyntaxKind.Identifier;
 }