[RFC] chore: Don't name externals in mergeExternals

packages/typegpu/src/core/resolve/externals.ts

@@ -1,6 +1,6 @@
 import { isLooseData } from '../../data/dataTypes.ts';
 import { isWgslStruct } from '../../data/wgslTypes.ts';
-import { getName, hasTinyestMetadata, setName } from '../../shared/meta.ts';
+import { getName, hasTinyestMetadata, isNamable, setName } from '../../shared/meta.ts';
 import { isWgsl, type ResolutionCtx } from '../../types.ts';
 
 /**
@@ -42,15 +42,6 @@ export function mergeExternals(existing: ExternalMap, newExternals: ExternalMap)
     } else {
       existing[key] = value;
     }
-
-    // Giving name to external value, if it does not already have one.
-    if (
-      value &&
-      (typeof value === 'object' || typeof value === 'function') &&
-      getName(value) === undefined
-    ) {
-      setName(value, key);
-    }
   }
 }
 
@@ -115,6 +106,9 @@ export function replaceExternalsInWgsl(
     }
 
     if (isResolvable(external)) {
+      if (isNamable(external) && getName(external) === undefined) {
+        setName(external, externalName.split('.').at(-1) as string);
+      }
       return acc.replaceAll(externalRegex, ctx.resolve(external).value);
     }
 

packages/typegpu/src/core/root/init.ts

@@ -95,7 +95,7 @@ import { vec3f, vec3u } from '../../data/vector.ts';
 import { u32 } from '../../data/numeric.ts';
 import { ceil } from '../../std/numeric.ts';
 import { allEq } from '../../std/boolean.ts';
-import { setName } from '../../shared/meta.ts';
+import { getName, setName } from '../../shared/meta.ts';
 
 /**
  * Changes the given array to a vec of 3 numbers, filling missing values with 1.
@@ -259,6 +259,9 @@ class WithBindingImpl implements WithBinding {
 
     const workgroupSize = workgroupSizeConfigs[callback.length] as v3u;
     const wrappedCallback = fn([u32, u32, u32])(callback as (...args: number[]) => void);
+    if (getName(wrappedCallback) === undefined) {
+      wrappedCallback.$name('wrappedCallback');
+    }
 
     const sizeUniform = root.createUniform(vec3u);
 

packages/typegpu/src/resolutionCtx.ts

@@ -51,7 +51,7 @@ import type {
 } from './types.ts';
 import { CodegenState, isSelfResolvable, NormalState } from './types.ts';
 import type { WgslEnableExtension } from './wgslExtensions.ts';
-import { getName, hasTinyestMetadata, setName } from './shared/meta.ts';
+import { getName, hasTinyestMetadata, isNamable, setName } from './shared/meta.ts';
 import { FuncParameterType } from 'tinyest';
 import { accessProp } from './tgsl/accessProp.ts';
 import { createIoSchema } from './core/function/ioSchema.ts';
@@ -197,6 +197,9 @@ class ItemStateStackImpl implements ItemStateStack {
         }
 
         const external = layer.externalMap[id];
+        if (isNamable(external) && getName(external) === undefined) {
+          setName(external, id);
+        }
 
         if (external !== undefined && external !== null) {
           return coerceToSnippet(external);

packages/typegpu/src/tgsl/accessProp.ts

@@ -34,6 +34,7 @@ import { isKnownAtComptime } from '../types.ts';
 import { coerceToSnippet, numericLiteralToSnippet } from './generationHelpers.ts';
 import { InfixDispatch, infixOperators, type InfixOperatorName } from './infixDispatch.ts';
 import { accessStructProp } from './accessStructProp.ts';
+import { getName, isNamable, setName } from '../shared/meta.ts';
 
 const infixKinds = [
   'vec2f',
@@ -205,7 +206,11 @@ export function accessProp(target: Snippet, propName: string): Snippet | undefin
 
   if (isKnownAtComptime(target) || target.dataType === UnknownData) {
     // oxlint-disable-next-line typescript/no-explicit-any -- we either know exactly what it is, or have no idea at all
-    return coerceToSnippet((target.value as any)[propName]);
+    const prop = (target.value as any)[propName];
+    if (isNamable(prop) && getName(prop) === undefined) {
+      setName(prop, propName);
+    }
+    return coerceToSnippet(prop);
   }
 
   return undefined;

packages/typegpu/tests/rawFn.test.ts

@@ -539,6 +539,42 @@ describe('tgpu.fn with raw wgsl and missing types', () => {
           }"
     `);
   });
+
+  it('names resolved externals', () => {
+    const c1 = (() => tgpu.const(d.vec2u, d.vec2u(1)))(); // unnamed
+    const c2 = (() => tgpu.const(d.vec2u, d.vec2u(2)))(); // unnamed
+    const c3 = (() => tgpu.const(d.vec2u, d.vec2u(3)))(); // unnamed
+    const fn = tgpu.fn([])`() { 
+  let a = n1; 
+  let b = ext.n2; 
+  let c = ext.n3.x; 
+}`.$uses({
+      n1: c1,
+      ext: { n2: c2, n3: c3 },
+    });
+
+    expect(tgpu.resolve([fn])).toMatchInlineSnapshot(`
+      "const n1: vec2u = vec2u(1);
+
+      const n2: vec2u = vec2u(2);
+
+      const n3: vec2u = vec2u(3);
+
+      fn fn_1() { 
+        let a = n1; 
+        let b = n2; 
+        let c = n3.x; 
+      }"
+    `);
+  });
+
+  it("resolved externals's names stay the same", () => {
+    const c1 = (() => tgpu.const(d.vec2u, d.vec2u(1)))(); // unnamed
+    tgpu.resolve([tgpu.fn([])`() { let a = myConst; }`.$uses({ myConst: c1 })]);
+    tgpu.resolve([tgpu.fn([])`() { let a = otherName; }`.$uses({ otherName: c1 })]);
+
+    expect(getName(c1)).toMatchInlineSnapshot(`"myConst"`);
+  });
 });
 
 describe('tgpu.computeFn with raw string WGSL implementation', () => {

packages/typegpu/tests/tgslFn.test.ts

@@ -1077,4 +1077,36 @@ describe('tgsl fn when using plugin', () => {
       }"
     `);
   });
+
+  it('names used externals', () => {
+    const myConst = (() => tgpu.const(d.u32, 1))(); // unnamed
+    const fn = () => {
+      'use gpu';
+      return myConst.$;
+    };
+
+    expect(tgpu.resolve([fn])).toMatchInlineSnapshot(`
+      "const myConst: u32 = 1u;
+
+      fn fn_1() -> u32 {
+        return myConst;
+      }"
+    `);
+  });
+
+  it('names used nested externals', () => {
+    const EXT = { myConst: (() => tgpu.const(d.u32, 1))() /* unnamed */ };
+    const fn = () => {
+      'use gpu';
+      return EXT.myConst.$;
+    };
+
+    expect(tgpu.resolve([fn])).toMatchInlineSnapshot(`
+      "const myConst: u32 = 1u;
+
+      fn fn_1() -> u32 {
+        return myConst;
+      }"
+    `);
+  });
 });