From 0e64f26712eb72c55e46e1700a7ed77aa4357ab2 Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Tue, 6 Dec 2016 11:48:24 -0500
Subject: [PATCH] gather names during validation, for later deoncflicting (#88)

---
 compiler/index.js               |  4 ++--
 compiler/validate/html/index.js | 14 ++++++++++++++
 compiler/validate/index.js      | 11 +++++++----
 test/test.js                    |  4 +++-
 test/validator/names/input.html |  3 +++
 test/validator/names/names.json |  4 ++++
 6 files changed, 33 insertions(+), 7 deletions(-)
 create mode 100644 compiler/validate/html/index.js
 create mode 100644 test/validator/names/input.html
 create mode 100644 test/validator/names/names.json

diff --git a/compiler/index.js b/compiler/index.js
index 1ee0dcfa42..01d0685b9c 100644
--- a/compiler/index.js
+++ b/compiler/index.js
@@ -15,9 +15,9 @@ export function compile ( source, options = {} ) {
 		};
 	}
 
-	validate( parsed, source, options );
+	const { names } = validate( parsed, source, options );
 
-	return generate( parsed, source, options );
+	return generate( parsed, source, options, names );
 }
 
 export { parse, validate };
diff --git a/compiler/validate/html/index.js b/compiler/validate/html/index.js
new file mode 100644
index 0000000000..d7d7378fbd
--- /dev/null
+++ b/compiler/validate/html/index.js
@@ -0,0 +1,14 @@
+export default function validateHtml ( validator, html ) {
+	function visit ( node ) {
+		if ( node.type === 'EachBlock' ) {
+			if ( !~validator.names.indexOf( node.context ) ) validator.names.push( node.context );
+			if ( node.index && !~validator.names.indexOf( node.index ) ) validator.names.push( node.index );
+		}
+
+		if ( node.children ) {
+			node.children.forEach( visit );
+		}
+	}
+
+	html.children.forEach( visit );
+}
diff --git a/compiler/validate/index.js b/compiler/validate/index.js
index a2ee763a2c..89811421e5 100644
--- a/compiler/validate/index.js
+++ b/compiler/validate/index.js
@@ -1,4 +1,5 @@
 import validateJs from './js/index.js';
+import validateHtml from './html/index.js';
 import { getLocator } from 'locate-character';
 import getCodeFrame from '../utils/getCodeFrame.js';
 
@@ -39,16 +40,18 @@ export default function validate ( parsed, source, options ) {
 
 		templateProperties: {},
 
-		errors: [],
-		warnings: []
+		names: []
 	};
 
+	if ( parsed.html ) {
+		validateHtml( validator, parsed.html );
+	}
+
 	if ( parsed.js ) {
 		validateJs( validator, parsed.js );
 	}
 
 	return {
-		errors: validator.errors,
-		warnings: validator.warnings
+		names: validator.names
 	};
 }
diff --git a/test/test.js b/test/test.js
index 297406c72f..f53bef8a19 100644
--- a/test/test.js
+++ b/test/test.js
@@ -177,7 +177,7 @@ describe( 'svelte', () => {
 					const errors = [];
 					const warnings = [];
 
-					svelte.validate( parsed, input, {
+					const { names } = svelte.validate( parsed, input, {
 						onerror ( error ) {
 							errors.push({
 								message: error.message,
@@ -197,9 +197,11 @@ describe( 'svelte', () => {
 
 					const expectedErrors = tryToLoadJson( `test/validator/${dir}/errors.json` ) || [];
 					const expectedWarnings = tryToLoadJson( `test/validator/${dir}/warnings.json` ) || [];
+					const expectedNames = tryToLoadJson( `test/validator/${dir}/names.json` ) || [];
 
 					assert.deepEqual( errors, expectedErrors );
 					assert.deepEqual( warnings, expectedWarnings );
+					assert.deepEqual( names, expectedNames );
 				} catch ( err ) {
 					if ( err.name !== 'ParseError' ) throw err;
 
diff --git a/test/validator/names/input.html b/test/validator/names/input.html
new file mode 100644
index 0000000000..a944d5fec0
--- /dev/null
+++ b/test/validator/names/input.html
@@ -0,0 +1,3 @@
+{{#each things as thing, index}}
+	<p>{{index}}: {{thing}}</p>
+{{/each}}
diff --git a/test/validator/names/names.json b/test/validator/names/names.json
new file mode 100644
index 0000000000..01151a29fd
--- /dev/null
+++ b/test/validator/names/names.json
@@ -0,0 +1,4 @@
+[
+	"thing",
+	"index"
+]