fix(analyzer): ignore unclosed response bodies for http.Head calls

passes/bodyclose/bodyclose.go

@@ -177,6 +177,10 @@ func (r *runner) isopen(b *ssa.BasicBlock, i int) bool {
 		return false
 	}
 
+	if r.isHeadCall(call) {
+		return false
+	}
+
 	if r.responseHandledByDirective(call) {
 		return false
 	}
@@ -335,9 +339,38 @@ func (r *runner) getReqCall(instr ssa.Instruction) (*ssa.Call, bool) {
 		return nil, false
 	}
 
+	if r.isHeadCall(call) {
+		return nil, false
+	}
+
 	return call, true
 }
 
+func (r *runner) isHeadCall(call *ssa.Call) bool {
+	if call == nil {
+		return false
+	}
+	callee := call.Call.StaticCallee()
+	if callee == nil {
+		return false
+	}
+	if callee.Pkg == nil || callee.Pkg.Pkg.Path() != nethttpPath {
+		return false
+	}
+	if callee.Name() != "Head" {
+		return false
+	}
+	recv := callee.Signature.Recv()
+	if recv == nil {
+		return true
+	}
+	recvType := recv.Type()
+	if ptr, ok := recvType.(*types.Pointer); ok {
+		recvType = ptr.Elem()
+	}
+	return isNamedType(recvType, nethttpPath, "Client")
+}
+
 func (r *runner) getResVal(instr ssa.Instruction) (ssa.Value, bool) {
 	switch instr := instr.(type) {
 	case *ssa.FieldAddr:

passes/bodyclose/testdata/src/a/issue78.go

@@ -0,0 +1,122 @@
+package a
+
+import (
+	"net/http"
+)
+
+type CustomClient struct {
+	*http.Client
+}
+
+func issue78HeadPackage() {
+	resp, err := http.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78HeadPackageUnassigned() {
+	http.Head("http://example.com/") // OK
+}
+
+func issue78HeadPackageDiscard() {
+	_, err := http.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+}
+
+func issue78HeadClientPointer() {
+	client := &http.Client{}
+	resp, err := client.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78HeadClientValue() {
+	var client http.Client
+	resp, err := client.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78HeadDefaultClient() {
+	resp, err := http.DefaultClient.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78HeadClientUnassigned() {
+	client := &http.Client{}
+	client.Head("http://example.com/") // OK
+}
+
+func issue78HeadWithClose() {
+	resp, err := http.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	defer resp.Body.Close()
+}
+
+func issue78HeadCustomClient() {
+	cc := &CustomClient{Client: &http.Client{}}
+	resp, err := cc.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78HeadReadBody() {
+	resp, err := http.Head("http://example.com/") // OK
+	if err != nil {
+		return
+	}
+	buf := make([]byte, 10)
+	resp.Body.Read(buf)
+}
+
+func issue78HeadInClosure() {
+	go func() {
+		resp, err := http.Head("http://example.com/") // OK
+		if err != nil {
+			return
+		}
+		_ = resp.StatusCode
+	}()
+}
+
+func issue78HeadLoop() {
+	for i := 0; i < 3; i++ {
+		resp, err := http.Head("http://example.com/") // OK
+		if err != nil {
+			continue
+		}
+		_ = resp.StatusCode
+	}
+}
+
+func issue78GetStillReported() {
+	resp, err := http.Get("http://example.com/") // want "response body must be closed"
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}
+
+func issue78ClientGetStillReported() {
+	client := &http.Client{}
+	resp, err := client.Get("http://example.com/") // want "response body must be closed"
+	if err != nil {
+		return
+	}
+	_ = resp.Header
+}