test: add apt warning regression coverage

src/cmd/apt_query/testlogs/testnormalizedlist_virtualpackagesexists_stdoutsconcretepackage.log

@@ -10,7 +10,7 @@
 EXECUTION-OBJ-END
 2025/03/15 22:29:14 EXECUTION-OBJ-START
 {
- "Cmd": "bash -c apt-cache showpkg libvips | grep -A 1 \"Reverse Provides\" | tail -1",
+ "Cmd": "apt-cache showpkg libvips",
  "Stdout": "libvips42 8.9.1-2 (= )\n",
  "Stderr": "",
  "CombinedOut": "libvips42 8.9.1-2 (= )\n",

src/internal/common/apt.go

@@ -33,20 +33,33 @@ func isErrLine(line string) bool {
 
 // Resolves virtual packages names to their concrete one.
 func getNonVirtualPackage(executor exec.Executor, name string) (pkg *AptPackage, err error) {
-	execution := executor.Exec("bash", "-c", fmt.Sprintf("apt-cache showpkg %s | grep -A 1 \"Reverse Provides\" | tail -1", name))
+	execution := executor.Exec("apt-cache", "showpkg", name)
 	err = execution.Error()
 	if err != nil {
 		logging.Fatal(err)
 		return pkg, err
 	}
-	if isErrLine(execution.CombinedOut) {
-		return pkg, execution.Error()
+
+	inReverseProvides := false
+	for _, line := range strings.Split(execution.CombinedOut, "\n") {
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" {
+			continue
+		}
+		if trimmed == "Reverse Provides:" {
+			inReverseProvides = true
+			continue
+		}
+		if !inReverseProvides || strings.HasPrefix(trimmed, "W: ") || isErrLine(trimmed) {
+			continue
+		}
+		splitLine := GetSplitLine(trimmed, " ", 3)
+		if len(splitLine.Words) < 2 {
+			continue
+		}
+		return &AptPackage{Name: splitLine.Words[0], Version: splitLine.Words[1]}, nil
 	}
-	splitLine := GetSplitLine(execution.CombinedOut, " ", 3)
-	if len(splitLine.Words) < 2 {
-		return pkg, fmt.Errorf("unable to parse space delimited line's package name and version from apt-cache showpkg output below:\n%s", execution.CombinedOut)
-	}
-	return &AptPackage{Name: splitLine.Words[0], Version: splitLine.Words[1]}, nil
+	return pkg, fmt.Errorf("unable to parse reverse provides package name and version from apt-cache showpkg output below:\n%s", execution.CombinedOut)
 }
 
 func getPackage(executor exec.Executor, paragraph string) (pkg *AptPackage, err error) {

src/internal/common/apt_test.go

@@ -0,0 +1,53 @@
+package common
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	execpkg "awalsh128.com/cache-apt-pkgs-action/src/internal/exec"
+)
+
+type stubExecutor struct {
+	executions map[string]*execpkg.Execution
+}
+
+func (s stubExecutor) Exec(name string, arg ...string) *execpkg.Execution {
+	cmd := name + " " + strings.Join(arg, " ")
+	execution, ok := s.executions[cmd]
+	if !ok {
+		panic(fmt.Sprintf("unexpected command: %s", cmd))
+	}
+	return execution
+}
+
+func TestGetNonVirtualPackage_IgnoresWarningsAfterReverseProvides(t *testing.T) {
+	executor := stubExecutor{
+		executions: map[string]*execpkg.Execution{
+			"apt-cache showpkg libopenblas0-openmp": {
+				Cmd: "apt-cache showpkg libopenblas0-openmp",
+				CombinedOut: strings.Join([]string{
+					"Package: libopenblas0-openmp",
+					"Reverse Provides:",
+					"libopenblas0-openmp 0.3.26+ds-1ubuntu0.1 (= )",
+					"W: Unable to read /etc/apt/apt.conf.d/99github-actions - open (13: Permission denied)",
+					"",
+				}, "\n"),
+				ExitCode: 0,
+			},
+		},
+	}
+
+	pkg, err := getNonVirtualPackage(executor, "libopenblas0-openmp")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if pkg == nil {
+		t.Fatal("expected package but got nil")
+	}
+
+	expected := AptPackage{Name: "libopenblas0-openmp", Version: "0.3.26+ds-1ubuntu0.1"}
+	if *pkg != expected {
+		t.Fatalf("unexpected package.\nexpected: %+v\nactual: %+v", expected, *pkg)
+	}
+}