better error messages for shader compilation errors

Author: jakobhellermann

crates/bevy_render/src/pipeline/pipeline_compiler.rs

@@ -143,7 +143,7 @@ impl PipelineCompiler {
                 &specialized_descriptor.shader_stages.vertex,
                 &pipeline_specialization.shader_specialization,
             )
-            .unwrap();
+            .unwrap_or_else(|e| panic_shader_error(e));
         specialized_descriptor.shader_stages.vertex = specialized_vertex_shader.clone_weak();
         let mut specialized_fragment_shader = None;
         specialized_descriptor.shader_stages.fragment = specialized_descriptor
@@ -158,7 +158,7 @@ impl PipelineCompiler {
                         fragment,
                         &pipeline_specialization.shader_specialization,
                     )
-                    .unwrap();
+                    .unwrap_or_else(|e| panic_shader_error(e));
                 specialized_fragment_shader = Some(shader.clone_weak());
                 shader
             });
@@ -356,3 +356,10 @@ impl PipelineCompiler {
         Ok(())
     }
 }
+
+fn panic_shader_error(error: ShaderError) -> ! {
+    let msg = error.to_string();
+    let msg = msg.trim_end().trim_end_matches("Debug log:"); // if this matches, then there wasn't a debug log anyways
+    let msg = msg.trim_end();
+    panic!("{}\n", msg);
+}

crates/bevy_render/src/shader/shader.rs

@@ -24,12 +24,12 @@ pub enum ShaderStage {
 #[derive(Error, Debug)]
 pub enum ShaderError {
     /// Shader compilation error.
-    #[error("Shader compilation error: {0}")]
+    #[error("Shader compilation error:\n{0}")]
     Compilation(String),
 
     #[cfg(any(target_os = "ios", all(target_arch = "aarch64", target_os = "macos")))]
     /// shaderc error.
-    #[error("shaderc error")]
+    #[error("shaderc error: {}")]
     ShaderC(#[from] shaderc::Error),
 
     #[cfg(any(target_os = "ios", all(target_arch = "aarch64", target_os = "macos")))]