Handle empty variable names in namer (#1484)

* Handle empty variable names in namer

* Add glsl-in test with empty global name

src/proc/namer.rs

@@ -89,7 +89,13 @@ impl Namer {
 
     pub fn call_or(&mut self, label: &Option<String>, fallback: &str) -> String {
         self.call(match *label {
-            Some(ref name) => name,
+            Some(ref name) => {
+                if name.trim().is_empty() {
+                    fallback
+                } else {
+                    name
+                }
+            }
             None => fallback,
         })
     }

tests/in/glsl/empty-global-name.frag

@@ -0,0 +1,7 @@
+layout(set = 1, binding = 1) uniform TextureData {
+    vec4 material;
+};
+
+void main() {
+	vec2 coords = vec2(material.xy);
+}

tests/out/wgsl/empty-global-name-frag.wgsl

@@ -0,0 +1,21 @@
+[[block]]
+struct TextureData {
+    material: vec4<f32>;
+};
+
+[[group(1), binding(1)]]
+var<uniform> global: TextureData;
+
+fn main1() {
+    var coords: vec2<f32>;
+
+    let e2: vec4<f32> = global.material;
+    coords = vec2<f32>(e2.xy);
+    return;
+}
+
+[[stage(fragment)]]
+fn main() {
+    main1();
+    return;
+}