prevent comments inside statement being later appended to it

src/ast/analyse.js

@@ -47,9 +47,19 @@ export default function analyse ( ast, magicString, module ) {
 
 		let trailing = !!previousStatement;
 
+		// TODO surely this can be neater
 		// attach leading comment
 		do {
-			const comment = module.comments[ commentIndex ];
+			let comment = module.comments[ commentIndex ];
+
+			// prevent comments inside the previous statement being
+			// appended to it
+			if ( previousStatement ) {
+				while ( comment && comment.start < previousStatement.end ) {
+					commentIndex += 1;
+					comment = module.comments[ commentIndex ];
+				}
+			}
 
 			if ( !comment || ( comment.end > statement.start ) ) break;
 

test/form/block-comments/_config.js

@@ -0,0 +1,4 @@
+module.exports = {
+	description: 'block comments are printed correctly',
+	skip: true // work on this later
+};

test/form/block-comments/foo.js

@@ -0,0 +1,13 @@
+export default function foo () {
+	return embiggen( 6, 7 );
+}
+
+/**
+ * Embiggens a number
+ * @param {number} num - the number to embiggen
+ * @param {number} factor - the factor to embiggen it by
+ * @returns {number}
+ */
+function embiggen ( num, factor ) {
+	return num * factor;
+}

test/form/block-comments/main.js

@@ -0,0 +1,3 @@
+import foo from './foo';
+
+alert( foo() );

test/function/iife-comments/_config.js

@@ -0,0 +1,8 @@
+var assert = require( 'assert' );
+
+module.exports = {
+	description: 'does not wrongly append comments',
+	exports: function ( exports ) {
+		assert.equal( exports, 42 );
+	}
+}

test/function/iife-comments/main.js

@@ -0,0 +1,13 @@
+(function () {
+	console.log( '1' ) // not an ID. should fix!
+
+	/*
+	BLOCK COMMENT
+	*/
+
+	console.log( '2' );
+
+	// standalone comment
+})();
+
+export default 42;