interpreter/wasm,internal/filetypes: fix wasm awkwardness

There currently this comment in the code:

```
// The CUE command works just fine without this (how?),
// but the API tests require this for some reason.
```

Having a special case for "wasm" in the filetypes code doesn't seem
quite right, and it turns out that the fix is straightforward: add
knowledge to `internal/filetypes` about WASM files.

The WASM files that are added are then added to `OrphanedFiles` not
`UnknownFiles` because the files are not actually unknown any more, and
the names are entered as full path names so the search is slightly
different.

No behavior change should result from this refactor.

Signed-off-by: Roger Peppe <[email protected]>
Change-Id: Icc18d0770c3f12aecc1a6a3274778b5fdf24f4ab
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1197522
TryBot-Result: CUEcueckoo <[email protected]>
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Paul Jolly <[email protected]>

Author: rogpeppe

cue/interpreter/wasm/wasm.go

@@ -71,19 +71,19 @@ type compiler struct {
 // attribute and returns it as an [adt.Builtin] with the given function
 // name.
 func (c *compiler) Compile(funcName string, scope adt.Value, a *internal.Attr) (adt.Expr, errors.Error) {
-	file, err := fileName(a)
+	baseFile, err := fileName(a)
 	if err != nil {
 		return nil, errors.Promote(err, "invalid attribute")
 	}
 	// TODO: once we have position information, make this
 	// error more user-friendly by returning the position.
-	if !strings.HasSuffix(file, "wasm") {
-		return nil, errors.Newf(token.NoPos, "load %q: invalid file name", file)
+	if !strings.HasSuffix(baseFile, "wasm") {
+		return nil, errors.Newf(token.NoPos, "load %q: invalid file name", baseFile)
 	}
 
-	file, found := findFile(file, c.b)
+	file, found := findFile(baseFile, c.b)
 	if !found {
-		return nil, errors.Newf(token.NoPos, "load %q: file not found", file)
+		return nil, errors.Newf(token.NoPos, "load %q: file not found", baseFile)
 	}
 
 	inst, err := c.instance(file)
@@ -118,16 +118,15 @@ func (c *compiler) instance(filename string) (inst *instance, err error) {
 	return inst, nil
 }
 
-// findFile searches the build.Instance for name. If found, it returnes
-// its full path name and true, otherwise it returns the original name
-// and false.
+// findFile searches the build.Instance for the given file name
+// and reports its full name and whether it was found.
 func findFile(name string, b *build.Instance) (path string, found bool) {
-	for _, f := range b.UnknownFiles {
-		if f.Filename == name {
-			return filepath.Join(b.Dir, name), true
+	for _, f := range b.OrphanedFiles {
+		if filepath.Base(f.Filename) == name {
+			return f.Filename, true
 		}
 	}
-	return name, false
+	return "", false
 }
 
 // fileName returns the file name of the external module specified in a,

cue/interpreter/wasm/wasm_test.go

@@ -54,17 +54,6 @@ func TestWasm(t *testing.T) {
 
 		bi := t.Instance()
 
-		// the BuildInstance created above doesn't know about
-		// the .wasm files (why not?), so add them here.
-		for _, f := range t.Archive.Files {
-			if strings.HasSuffix(f.Name, ".wasm") {
-				bf := &build.File{
-					Filename: f.Name,
-				}
-				bi.UnknownFiles = append(bi.UnknownFiles, bf)
-			}
-		}
-
 		v := ctx.BuildInstance(bi)
 		err := v.Validate()
 

internal/filetypes/filetypes.go

@@ -182,16 +182,6 @@ func ParseArgs(args []string) (files []*build.File, err error) {
 					continue
 				}
 
-				// The CUE command works just fine without this (how?),
-				// but the API tests require this for some reason.
-				//
-				// This is almost certainly wrong, and in the wrong place.
-				//
-				// TODO(aram): why do we need this here?
-				if len(a) == 1 && strings.HasSuffix(a[0], ".wasm") {
-					continue
-				}
-
 				modeVal, fileVal, err = parseType("", Input)
 				if err != nil {
 					return nil, err

internal/filetypes/types.cue

@@ -170,6 +170,7 @@ modes: [string]: {
 		".yml":       tags.yaml
 		".txt":       tags.text
 		".go":        tags.go
+		".wasm":      tags.binary
 		".proto":     tags.proto
 		".textproto": tags.textproto
 		".textpb":    tags.textproto // perhaps also pbtxt