Merge 9371bcfb56 into 939d65bc16

Related to #34

.goreleaser.yaml

@@ -1,12 +1,6 @@
-# This is an example .goreleaser.yml file with some sensible defaults.
-# Make sure to check the documentation at https://goreleaser.com
-
-# The lines below are called `modelines`. See `:help modeline`
-# Feel free to remove those if you don't want/need to use them.
 # yaml-language-server: $schema=https://goreleaser.com/static/schema.json
 # vim: set ts=2 sw=2 tw=0 fo=cnqoj
-
-version: 1
+version: 2
 
 force_token: github
 
@@ -45,3 +39,6 @@ changelog:
     exclude:
       - "^docs:"
       - "^test:"
+
+release:
+  draft: true

pkg/analyzer/analyzer.go

@@ -7,7 +7,7 @@ import (
 	"go/ast"
 	"go/printer"
 	"go/token"
-	"go/types"
+	"slices"
 
 	"golang.org/x/tools/go/analysis"
 	"golang.org/x/tools/go/analysis/passes/inspect"
@@ -30,6 +30,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 		(*ast.ForStmt)(nil),
 		(*ast.RangeStmt)(nil),
 		(*ast.FuncLit)(nil),
+		(*ast.FuncDecl)(nil),
 	}
 
 	inspctr.Preorder(nodeFilter, func(node ast.Node) {
@@ -81,25 +82,23 @@ func getReportMessage(node ast.Node) string {
 		return "nested context in loop"
 	case *ast.FuncLit:
 		return "nested context in function literal"
+	case *ast.FuncDecl:
+		return "potential nested context in function declaration"
 	default:
 		return "unsupported nested context type"
 	}
 }
 
 func getBody(node ast.Node) (*ast.BlockStmt, error) {
-	forStmt, ok := node.(*ast.ForStmt)
-	if ok {
-		return forStmt.Body, nil
-	}
-
-	rangeStmt, ok := node.(*ast.RangeStmt)
-	if ok {
-		return rangeStmt.Body, nil
-	}
-
-	funcLit, ok := node.(*ast.FuncLit)
-	if ok {
-		return funcLit.Body, nil
+	switch typedNode := node.(type) {
+	case *ast.ForStmt:
+		return typedNode.Body, nil
+	case *ast.RangeStmt:
+		return typedNode.Body, nil
+	case *ast.FuncLit:
+		return typedNode.Body, nil
+	case *ast.FuncDecl:
+		return typedNode.Body, nil
 	}
 
 	return nil, errUnknown
@@ -108,44 +107,29 @@ func getBody(node ast.Node) (*ast.BlockStmt, error) {
 func findNestedContext(pass *analysis.Pass, node ast.Node, stmts []ast.Stmt) *ast.AssignStmt {
 	for _, stmt := range stmts {
 		// Recurse if necessary
-		if inner, ok := stmt.(*ast.BlockStmt); ok {
-			found := findNestedContext(pass, node, inner.List)
-			if found != nil {
+		switch typedStmt := stmt.(type) {
+		case *ast.BlockStmt:
+			if found := findNestedContext(pass, node, typedStmt.List); found != nil {
 				return found
 			}
-		}
-
-		if inner, ok := stmt.(*ast.IfStmt); ok {
-			found := findNestedContext(pass, node, inner.Body.List)
-			if found != nil {
+		case *ast.IfStmt:
+			if found := findNestedContext(pass, node, typedStmt.Body.List); found != nil {
 				return found
 			}
-		}
-
-		if inner, ok := stmt.(*ast.SwitchStmt); ok {
-			found := findNestedContext(pass, node, inner.Body.List)
-			if found != nil {
+		case *ast.SwitchStmt:
+			if found := findNestedContext(pass, node, typedStmt.Body.List); found != nil {
 				return found
 			}
-		}
-
-		if inner, ok := stmt.(*ast.CaseClause); ok {
-			found := findNestedContext(pass, node, inner.Body)
-			if found != nil {
+		case *ast.CaseClause:
+			if found := findNestedContext(pass, node, typedStmt.Body); found != nil {
 				return found
 			}
-		}
-
-		if inner, ok := stmt.(*ast.SelectStmt); ok {
-			found := findNestedContext(pass, node, inner.Body.List)
-			if found != nil {
+		case *ast.SelectStmt:
+			if found := findNestedContext(pass, node, typedStmt.Body.List); found != nil {
 				return found
 			}
-		}
-
-		if inner, ok := stmt.(*ast.CommClause); ok {
-			found := findNestedContext(pass, node, inner.Body)
-			if found != nil {
+		case *ast.CommClause:
+			if found := findNestedContext(pass, node, typedStmt.Body); found != nil {
 				return found
 			}
 		}
@@ -169,13 +153,14 @@ func findNestedContext(pass *analysis.Pass, node ast.Node, stmts []ast.Stmt) *as
 			continue
 		}
 
+		// Ignore [context.Background] & [context.TODO].
+		if isContextFunction(assignStmt.Rhs[0], "Background", "TODO") {
+			continue
+		}
+
 		// allow assignment to non-pointer children of values defined within the loop
-		if lhs := getRootIdent(pass, assignStmt.Lhs[0]); lhs != nil {
-			if obj := pass.TypesInfo.ObjectOf(lhs); obj != nil {
-				if checkObjectScopeWithinNode(obj.Parent(), node) {
-					continue // definition is within the loop
-				}
-			}
+		if isWithinLoop(assignStmt.Lhs[0], node, pass) {
+			continue
 		}
 
 		return assignStmt
@@ -184,16 +169,51 @@ func findNestedContext(pass *analysis.Pass, node ast.Node, stmts []ast.Stmt) *as
 	return nil
 }
 
-func checkObjectScopeWithinNode(scope *types.Scope, node ast.Node) bool {
+// render returns the pretty-print of the given node
+func render(fset *token.FileSet, x interface{}) ([]byte, error) {
+	var buf bytes.Buffer
+	if err := printer.Fprint(&buf, fset, x); err != nil {
+		return nil, fmt.Errorf("printing node: %w", err)
+	}
+	return buf.Bytes(), nil
+}
+
+func isContextFunction(exp ast.Expr, fnName ...string) bool {
+	call, ok := exp.(*ast.CallExpr)
+	if !ok {
+		return false
+	}
+
+	selector, ok := call.Fun.(*ast.SelectorExpr)
+	if !ok {
+		return false
+	}
+
+	ident, ok := selector.X.(*ast.Ident)
+	if !ok {
+		return false
+	}
+
+	return ident.Name == "context" && slices.Contains(fnName, selector.Sel.Name)
+}
+
+func isWithinLoop(exp ast.Expr, node ast.Node, pass *analysis.Pass) bool {
+	lhs := getRootIdent(pass, exp)
+	if lhs == nil {
+		return false
+	}
+
+	obj := pass.TypesInfo.ObjectOf(lhs)
+	if obj == nil {
+		return false
+	}
+
+	scope := obj.Parent()
 	if scope == nil {
 		return false
 	}
 
-	if scope.Pos() >= node.Pos() && scope.End() <= node.End() {
-		return true
-	}
-
-	return false
+	return scope.Pos() >= node.Pos() && scope.End() <= node.End()
 }
 
 func getRootIdent(pass *analysis.Pass, node ast.Node) *ast.Ident {
@@ -213,12 +233,3 @@ func getRootIdent(pass *analysis.Pass, node ast.Node) *ast.Ident {
 		}
 	}
 }
-
-// render returns the pretty-print of the given node
-func render(fset *token.FileSet, x interface{}) ([]byte, error) {
-	var buf bytes.Buffer
-	if err := printer.Fprint(&buf, fset, x); err != nil {
-		return nil, fmt.Errorf("printing node: %w", err)
-	}
-	return buf.Bytes(), nil
-}

testdata/src/example.go

@@ -1,6 +1,9 @@
 package src
 
-import "context"
+import (
+	"context"
+	"testing"
+)
 
 func example() {
 	ctx := context.Background()
@@ -228,3 +231,43 @@ func okMiddleware2(ctx context.Context) func(ctx context.Context) error {
 func doSomethingWithCtx(ctx context.Context) error {
 	return nil
 }
+
+func testCasesInit(t *testing.T) {
+	cases := []struct {
+		ctx context.Context
+	}{
+		{},
+		{
+			ctx: context.WithValue(context.Background(), "key", "value"),
+		},
+	}
+	for _, tc := range cases {
+		t.Run("some test", func(t *testing.T) {
+			if tc.ctx == nil {
+				tc.ctx = context.Background()
+			}
+		})
+	}
+}
+
+type Container struct {
+	Ctx context.Context
+}
+
+func something() func(*Container) {
+	return func(r *Container) {
+		ctx := r.Ctx
+		ctx = context.WithValue(ctx, "key", "val")
+		r.Ctx = ctx // want "nested context in function literal"
+	}
+}
+
+func other() func(*Container) {
+	return blah
+}
+
+func blah(r *Container) {
+	ctx := r.Ctx
+	ctx = context.WithValue(ctx, "key", "val")
+	r.Ctx = ctx // want "potential nested context in function declaration"
+}