Add 'trailing' mode to parameter-properties (#28)

Author: cjc343

docs/parameter-properties.md

@@ -12,6 +12,7 @@ Usage:
   true,
   "all-or-none",   // forces all or none of a constructors parameters to be parameter properties
   "leading",       // forces parameter properties to precede regular parameters
+  "trailing",      // forces regular parameters to precede parameter properties
   "member-access", // forces an access modifier for every parameter property
   "readonly"       // forces all parameter properties to be readonly
 ]

rules/parameterPropertiesRule.ts

@@ -6,11 +6,13 @@ import { AbstractConfigDependentRule } from '../src/rules';
 
 const ALL_OR_NONE_OPTION = 'all-or-none';
 const LEADING_OPTION = 'leading';
+const TRAILING_OPTION = 'trailing';
 const READONLY_OPTION = 'readonly';
 const MEMBER_ACCESS_OPTION = 'member-access';
 
 const ALL_OR_NONE_FAIL = 'don\'t mix parameter properties with regular parameters';
 const LEADING_FAIL = 'parameter properties must precede regular parameters';
+const TRAILING_FAIL = 'regular parameters must precede parameter properties';
 const READONLY_FAIL = 'parameter property must be readonly';
 const MEMBER_ACCESS_FAIL = 'parameter property must have access modifier';
 
@@ -26,6 +28,7 @@ const MEMBER_ACCESS_FAIL = 'parameter property must have access modifier';
 interface IOptions {
     allOrNone: boolean;
     leading: boolean;
+    trailing: boolean;
     readOnly: boolean;
     memberAccess: boolean;
 }
@@ -35,6 +38,7 @@ export class Rule extends AbstractConfigDependentRule {
         return this.applyWithWalker(new ParameterPropertyWalker(sourceFile, this.ruleName, {
             allOrNone: this.ruleArguments.indexOf(ALL_OR_NONE_OPTION) !== -1,
             leading: this.ruleArguments.indexOf(LEADING_OPTION) !== -1,
+            trailing: this.ruleArguments.indexOf(TRAILING_OPTION) !== -1,
             readOnly: this.ruleArguments.indexOf(READONLY_OPTION) !== -1,
             memberAccess: this.ruleArguments.indexOf(MEMBER_ACCESS_OPTION) !== -1,
         }));
@@ -90,6 +94,10 @@ class ParameterPropertyWalker extends Lint.AbstractWalker<IOptions> {
                     regular = true;
                 }
             }
+        } else if (this.options.trailing) {
+            for (let i = index; i < length; ++i)
+                if (!utils.isParameterProperty(parameters[i]))
+                    this.addFailureAtNode(parameters[i], TRAILING_FAIL);
         }
 
         if (this.options.memberAccess) {

test/rules/parameter-properties/trailing/test.ts.lint

@@ -0,0 +1,27 @@
+class Foo {
+    constructor(foo: string, public bar: number, readonly baz?) {}
+}
+
+class Bar {
+    constructor() {}
+}
+
+class Baz {
+    constructor(bas) {}
+}
+
+class Bas {
+    constructor(readonly baz) {}
+}
+
+class Quux {
+    constructor(protected foo, bar) {}
+                               ~~~ [fail]
+}
+
+class Ajaff {
+    constructor(private foo, bar, public baz) {}
+                             ~~~ [fail]
+}
+
+[fail]: regular parameters must precede parameter properties

test/rules/parameter-properties/trailing/tslint.json

@@ -0,0 +1,9 @@
+{
+  "rulesDirectory": "../../../../rules",
+  "rules": {
+    "parameter-properties": [
+      true,
+      "trailing"
+    ]
+  }
+}