fix alias handling and upgrade to go >=1.24

.github/workflows/ci.yml

@@ -4,7 +4,7 @@ jobs:
   all:
     strategy:
       matrix:
-        go-version: [1.18, 1.19, 1.x]
+        go-version: ["1.24", "1.25", "1.x"]
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
 
@@ -20,24 +20,10 @@ jobs:
     - name: build
       run: make build
 
-    # For earlier go versions, staticcheck build fails due to:
-    #
-    #  ../../../go/pkg/mod/honnef.co/go/tools@v0.3.3/go/ir/builder.go:36:2:
-    #  //go:build comment without // +build comment
-    #
-    # or due to:
-    #
-    #  ../../../go/pkg/mod/honnef.co/go/tools@v0.4.3/staticcheck/lint.go:4030:36:
-    #  sel.Obj().(*types.Func).Origin undefined (type *types.Func has no field
-    #  or method Origin)
-    #  note: module requires Go 1.19
-    #
-    - name: install vet tools (go 1.19 or later)
-      if: ${{ matrix.go-version >= '1.19' }}
+    - name: install vet tools
       run: make install-vet
 
-    - name: vet (go 1.19 or later)
-      if: ${{ matrix.go-version >= '1.19' }}
+    - name: vet
       run: make vet
 
     - name: test

Makefile

@@ -24,15 +24,13 @@ cover:
 
 .PHONY: install-vet
 install-vet:
-	go install github.com/nishanths/exhaustive/cmd/exhaustive@latest
 	go install github.com/gordonklaus/ineffassign@latest
 	go install github.com/kisielk/errcheck@latest
 	go install honnef.co/go/tools/cmd/staticcheck@latest
 
 .PHONY: vet
 vet:
 	go vet ./...
-	exhaustive ./...
 	ineffassign ./...
 	errcheck ./...
 	staticcheck -checks="inherit,-S1034" ./...

common.go

@@ -73,6 +73,9 @@ func fromTypeParam(pass *analysis.Pass, tp *types.TypeParam, typeparam bool) (re
 
 func fromType(pass *analysis.Pass, t types.Type, typeparam bool) (result []enumTypeAndMembers, ok bool) {
 	switch t := t.(type) {
+	case *types.Alias:
+		return fromType(pass, types.Unalias(t), typeparam)
+
 	case *types.Named:
 		return fromNamed(pass, t, typeparam)
 

enum.go

@@ -144,7 +144,7 @@ func possibleEnumMember(constName *ast.Ident, info *types.Info) (et enumType, na
 		return enumType{}, "", "", false
 	}
 
-	named := obj.Type().(*types.Named) // guaranteed by validNamedBasic
+	named := types.Unalias(obj.Type()).(*types.Named) // guaranteed by validNamedBasic
 	tn := named.Obj()
 
 	// By definition, enum type's scope and enum member's scope must be the
@@ -216,8 +216,9 @@ func hasIgnoreDecl(pass *analysis.Pass, doc *ast.CommentGroup) bool {
 //
 // The following is guaranteed:
 //
-//	validNamedBasic(t) == true => t.(*types.Named)
+//	validNamedBasic(t) == true => types.Unalias(t).(*types.Named)
 func validNamedBasic(t types.Type) bool {
+	t = types.Unalias(t)
 	named, ok := t.(*types.Named)
 	if !ok {
 		return false

go.mod

@@ -1,7 +1,10 @@
 module github.com/nishanths/exhaustive
 
-go 1.18
+go 1.24.0
 
-require golang.org/x/tools v0.18.0
+require golang.org/x/tools v0.38.0
 
-require golang.org/x/mod v0.15.0 // indirect
+require (
+	golang.org/x/mod v0.29.0 // indirect
+	golang.org/x/sync v0.17.0 // indirect
+)

go.sum

@@ -1,5 +1,8 @@
-golang.org/x/mod v0.15.0 h1:SernR4v+D55NyBH2QiEQrlBAnj1ECL6AGrA5+dPaMY8=
-golang.org/x/mod v0.15.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
-golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
-golang.org/x/tools v0.18.0 h1:k8NLag8AGHnn+PHbl7g43CtqZAwG60vZkLqgyZgIHgQ=
-golang.org/x/tools v0.18.0/go.mod h1:GL7B4CwcLLeo59yx/9UWWuNOW1n3VZ4f5axWfML7Lcg=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+golang.org/x/mod v0.29.0 h1:HV8lRxZC4l2cr3Zq1LvtOsi/ThTgWnUk/y64QSs8GwA=
+golang.org/x/mod v0.29.0/go.mod h1:NyhrlYXJ2H4eJiRy/WDBO6HMqZQ6q9nk4JzS3NuCK+w=
+golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
+golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/tools v0.38.0 h1:Hx2Xv8hISq8Lm16jvBZ2VQf+RLmbd7wVUsALibYI/IQ=
+golang.org/x/tools v0.38.0/go.mod h1:yEsQ/d/YK8cjh0L6rZlY8tgtlKiBNTL14pGDJPJpYQs=

map.go

@@ -34,16 +34,18 @@ func mapChecker(pass *analysis.Pass, cfg mapConfig, generated boolCache, comment
 
 		lit := n.(*ast.CompositeLit)
 
-		mapType, ok := pass.TypesInfo.Types[lit.Type].Type.(*types.Map)
-		if !ok {
-			namedType, ok2 := pass.TypesInfo.Types[lit.Type].Type.(*types.Named)
-			if !ok2 {
-				return true, resultNotMapLiteral
-			}
-			mapType, ok = namedType.Underlying().(*types.Map)
+		var mapType *types.Map
+		switch tt := types.Unalias(pass.TypesInfo.Types[lit.Type].Type).(type) {
+		case *types.Map:
+			mapType = tt
+		case *types.Named:
+			var ok bool
+			mapType, ok = tt.Underlying().(*types.Map)
 			if !ok {
 				return true, resultNotMapLiteral
 			}
+		default:
+			return true, resultNotMapLiteral
 		}
 
 		if len(lit.Elts) == 0 {