From 808af545e33f0140dd82849b4234a1614a57a09c Mon Sep 17 00:00:00 2001
From: Tom Lauwaerts <tom.lauwaerts@vub.be>
Date: Thu, 13 Aug 2026 14:45:10 +0200
Subject: [PATCH] Support prebuild wasm

---
 src/manage/Compiler.ts            | 11 +++++++++++
 src/sourcemap/SourceMapFactory.ts |  5 +++++
 2 files changed, 16 insertions(+)

diff --git a/src/manage/Compiler.ts b/src/manage/Compiler.ts
index 7a0282d..fd92b49 100644
--- a/src/manage/Compiler.ts
+++ b/src/manage/Compiler.ts
@@ -25,10 +25,12 @@ export interface CompileOutput {
 
 export class CompilerFactory {
     private readonly wat: WatCompiler;
+    private readonly wasm: WasmCompiler;
     private readonly asc: AsScriptCompiler;
 
     constructor(wabt: string) {
         this.wat = new WatCompiler(wabt);
+        this.wasm = new WasmCompiler(wabt);
         this.asc = new AsScriptCompiler(wabt);
     }
 
@@ -38,6 +40,8 @@ export class CompilerFactory {
             case 'wast' :
             case 'wat' :
                 return this.wat;
+            case 'wasm' :
+                return this.wasm;
             case 'ts' :
                 return this.asc;
         }
@@ -150,6 +154,13 @@ export class WatCompiler extends Compiler {
     }
 }
 
+/** A precompiled WebAssembly module can be uploaded without recompilation. */
+export class WasmCompiler extends WatCompiler {
+    public compile(program: string, _dir?: string): Promise<CompileOutput> {
+        return Promise.resolve({file: program});
+    }
+}
+
 export class AsScriptCompiler extends Compiler {
     private readonly wabt: string;
 
diff --git a/src/sourcemap/SourceMapFactory.ts b/src/sourcemap/SourceMapFactory.ts
index 67efb64..b48fb18 100644
--- a/src/sourcemap/SourceMapFactory.ts
+++ b/src/sourcemap/SourceMapFactory.ts
@@ -20,6 +20,11 @@ export class SourceMapFactory {
             case 'wat' :
                 compiled = await this.compilerFactory.pickCompiler(source).compile(source);
                 return new WatMapper(compiled.out ?? '', tmpdir ?? path.dirname(compiled.file), WABT).mapping();
+            case 'wasm' :
+                // Precompiled modules do not carry a WAT source mapping. The
+                // module can still be executed; requests that need source
+                // locations simply have no mapping to resolve against.
+                return new SourceMap.Mapping();
             case 'ts' :
                 return new AsScriptMapper(source ?? '', tmpdir ?? path.dirname(source)).mapping();
         }