add codegen support for raw mustache tags

compiler/generate/visitors/RawMustacheTag.js

@@ -0,0 +1,47 @@
+import deindent from '../utils/deindent.js';
+
+export default {
+	enter ( generator, node ) {
+		const name = generator.current.counter( 'raw' );
+
+		generator.addSourcemapLocations( node.expression );
+		const { snippet } = generator.contextualise( node.expression );
+
+		// we would have used comments here, but the `insertAdjacentHTML` api only
+		// exists for `Element`s.
+		const before = `${name}_before`;
+		generator.addElement( before, `document.createElement( 'noscript' )`, true );
+		const after = `${name}_after`;
+		generator.addElement( after, `document.createElement( 'noscript' )`, true );
+
+		const isToplevel = generator.current.localElementDepth === 0;
+
+		const mountStatement = deindent`
+			${before}.insertAdjacentHTML( 'afterend', ${snippet} );
+		`;
+		const detachStatement = deindent`
+			while ( ${before}.nextSibling && ${before}.nextSibling !== ${after} ) {
+				${before}.parentNode.removeChild( ${before}.nextSibling );
+			}
+		`;
+
+		if ( isToplevel ) { 
+			generator.current.mountStatements.push(mountStatement);
+		} else {
+			generator.current.initStatements.push(mountStatement);
+		}
+
+		generator.current.updateStatements.push( deindent`
+			${detachStatement}
+			${mountStatement}
+		` );
+
+		if ( isToplevel ) {
+			const { detachStatements } = generator.current;
+			// we need `before` and `after` to still be in the DOM when running the
+			// detach code, so splice in the detach code *before* detaching
+			// `before`/`after`.
+			detachStatements.splice( detachStatements.length - 2, 0, detachStatement);
+		}
+	}
+};

compiler/generate/visitors/index.js

@@ -3,6 +3,7 @@ import EachBlock from './EachBlock.js';
 import Element from './Element.js';
 import IfBlock from './IfBlock.js';
 import MustacheTag from './MustacheTag.js';
+import RawMustacheTag from './RawMustacheTag.js';
 import Text from './Text.js';
 import YieldTag from './YieldTag.js';
 
@@ -12,6 +13,7 @@ export default {
 	Element,
 	IfBlock,
 	MustacheTag,
+	RawMustacheTag,
 	Text,
 	YieldTag
 };

test/compiler/raw-mustaches/_config.js

@@ -0,0 +1,16 @@
+const ns = '<noscript></noscript>';
+export default {
+	data: {
+		raw: '<span><em>raw html!!!\\o/</span></em>'
+	},
+	html: `before${ns}<span><em>raw html!!!\\o/</span></em>${ns}after`,
+
+	test ( assert, component, target ) {
+		component.set({ raw: '' });
+		assert.equal( target.innerHTML, `before${ns}${ns}after` );
+		component.set({ raw: 'how about <strong>unclosed elements?' });
+		assert.equal( target.innerHTML, `before${ns}how about <strong>unclosed elements?</strong>${ns}after` );
+		component.teardown();
+		assert.equal( target.innerHTML, '' );
+	}
+};

test/compiler/raw-mustaches/main.html

@@ -0,0 +1 @@
+before{{{raw}}}after