go/analysis: handle common nil pointers

Updates golang/go#33727, golang/go#33689

Change-Id: Ie32ac4efc9fe0d7b08fcff3feb44b28d83df942d
Reviewed-on: https://go-review.googlesource.com/c/tools/+/190908
Run-TryBot: Rebecca Stambler <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Michael Matloob <[email protected]>

Author: stamblerre

go/analysis/passes/ctrlflow/ctrlflow.go

@@ -102,10 +102,11 @@ func run(pass *analysis.Pass) (interface{}, error) {
 	inspect.Preorder(nodeFilter, func(n ast.Node) {
 		switch n := n.(type) {
 		case *ast.FuncDecl:
-			fn := pass.TypesInfo.Defs[n.Name].(*types.Func)
-			funcDecls[fn] = &declInfo{decl: n}
-			decls = append(decls, fn)
-
+			// Type information may be incomplete.
+			if fn, ok := pass.TypesInfo.Defs[n.Name].(*types.Func); ok {
+				funcDecls[fn] = &declInfo{decl: n}
+				decls = append(decls, fn)
+			}
 		case *ast.FuncLit:
 			funcLits[n] = new(litInfo)
 			lits = append(lits, n)

go/analysis/passes/structtag/structtag.go

@@ -40,7 +40,11 @@ func run(pass *analysis.Pass) (interface{}, error) {
 		(*ast.StructType)(nil),
 	}
 	inspect.Preorder(nodeFilter, func(n ast.Node) {
-		styp := pass.TypesInfo.Types[n.(*ast.StructType)].Type.(*types.Struct)
+		styp, ok := pass.TypesInfo.Types[n.(*ast.StructType)].Type.(*types.Struct)
+		// Type information may be incomplete.
+		if !ok {
+			return
+		}
 		var seen namesSeen
 		for i := 0; i < styp.NumFields(); i++ {
 			field := styp.Field(i)

internal/lsp/cache/pkg.go

@@ -177,7 +177,7 @@ func (pkg *pkg) GetTypesSizes() types.Sizes {
 }
 
 func (pkg *pkg) IsIllTyped() bool {
-	return pkg.types == nil && pkg.typesInfo == nil
+	return pkg.types == nil || pkg.typesInfo == nil || pkg.typesSizes == nil
 }
 
 func (pkg *pkg) SetDiagnostics(diags []source.Diagnostic) {

internal/lsp/source/analysis.go

@@ -168,7 +168,7 @@ func (act *Action) execOnce(ctx context.Context, fset *token.FileSet) error {
 	}
 	act.pass = pass
 
-	if act.Pkg.IsIllTyped() && !pass.Analyzer.RunDespiteErrors {
+	if act.Pkg.IsIllTyped() {
 		act.err = errors.Errorf("analysis skipped due to errors in package: %v", act.Pkg.GetErrors())
 	} else {
 		act.result, act.err = pass.Analyzer.Run(pass)