From e447e3a52b22fa35e60339d75a1ebf19fdbd8422 Mon Sep 17 00:00:00 2001
From: Andrew Ray <me@andrewray.me>
Date: Tue, 1 Jan 2019 15:18:30 -0800
Subject: [PATCH] Don't mark funciton argument struct names as declarations

Fixes
 - Issue #3
 - https://github.com/glslify/glsl-token-descope/issues/3
 - https://github.com/stackgl/glsl-parser/issues/24<Paste>
---
 index.js          | 13 +++++++++++++
 test/arguments.js |  6 ++++++
 2 files changed, 19 insertions(+)

diff --git a/index.js b/index.js
index c7ae273..5968525 100644
--- a/index.js
+++ b/index.js
@@ -64,6 +64,13 @@ function assigns(tokens) {
         idx++
         skipWhitespace(+1)
         if (tokens[idx].type !== 'ident') continue
+
+        // Handle the case of a parameter like "in StructName myArg", where if
+        // there's one ident after another, assume the one we're on is the
+        // StructName, identified in the higher scope, and not a declaration
+        var nextNonWhitespace = peekPastWhitespace()
+        if (nextNonWhitespace && nextNonWhitespace.type === 'ident') continue
+
         tokens[idx++].declaration = true
         skipWhitespace(+1)
         skipArrayDimensions()
@@ -143,6 +150,12 @@ function assigns(tokens) {
 
   return tokens
 
+  function peekPastWhitespace() {
+    var peekIdx = idx + 1;
+    while (tokens[peekIdx] && tokens[peekIdx].type === 'whitespace') peekIdx++
+    return tokens[peekIdx];
+  }
+
   function skipWhitespace(n) {
     while (tokens[idx] && tokens[idx].type === 'whitespace') idx++
   }
diff --git a/test/arguments.js b/test/arguments.js
index c318301..a3c8ad3 100644
--- a/test/arguments.js
+++ b/test/arguments.js
@@ -7,6 +7,10 @@ float aFunction(vec2 a, vec3 b, float c) {
   return z;
 }
 
+float sFunction(UserStruct structArg);
+float sFunction(const UserStruct structArg);
+float sFunction(const in UserStruct structArg);
+
 Thing xFunction(vec2 d, Thing e[2], Thing f, Thing g[2][5]);
 Thing xFunction(vec2 d, Thing e[2], Thing f, Thing g[2][5]) {
   Thing y = Thing(2.0);
@@ -34,5 +38,7 @@ Another yFunction(
   , i: [true]
   , j: [true]
   , k: [true]
+  , UserStruct: [false, false, false]
+  , structArg: [true, true, true]
   , Thing: new Array(10).map(() => false)
 }))