Resolve flag aliases in failed command routes

execute_reporting_test.go

@@ -92,6 +92,53 @@ func TestExecuteQuietUsageKeepsAliasGuidanceVisible(t *testing.T) {
 	}
 }
 
+func TestUnresolvedRoutesUseReportingAliasesForTheirParseContext(t *testing.T) {
+	calls := 0
+	command := NewCommand(CommandSpec[struct{}]{
+		Name:     "run",
+		NewInput: func() struct{} { calls++; return struct{}{} },
+		Run:      func(Invocation, struct{}) Outcome { calls++; return Success() },
+	})
+	app, err := New(Identity{Name: "Example"}, Group("group", "", Group("nested", "", command)),
+		FlagAlias("-d", "--debug"), FlagAlias("-q", "--quiet"),
+		FlagAlias("-x", "--quiet"), FlagAliasFor("group nested", "-x", "--debug"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, path := range [][]string{{"missing"}, {"group", "missing"}, {"group", "nested", "missing"}} {
+		t.Run(strings.Join(path, "/"), func(t *testing.T) {
+			var canonicalDiagnostics, aliasDiagnostics bytes.Buffer
+			canonical := app.Execute(context.Background(), append(append([]string(nil), path...), "--debug"), Streams{Err: &canonicalDiagnostics})
+			alias := app.Execute(context.Background(), append(append([]string(nil), path...), "-d"), Streams{Err: &aliasDiagnostics})
+			if canonical.Kind != OutcomeUsage || alias.Kind != OutcomeUsage || canonical.Status != alias.Status || canonical.Explanation.Message != alias.Explanation.Message {
+				t.Fatalf("canonical=%#v alias=%#v", canonical, alias)
+			}
+			for _, text := range []string{canonicalDiagnostics.String(), aliasDiagnostics.String()} {
+				if !strings.Contains(text, "DEBUG:") || !strings.Contains(text, "ERROR:") || strings.Contains(text, "unknown shorthand") || strings.Contains(text, "Alias for:") {
+					t.Fatalf("diagnostics=%q", text)
+				}
+			}
+			route := resolveEnteredRoute(path, app.routeSnapshot())
+			if route.kind != routeUnknown || len(route.canonicalPath) != 0 {
+				t.Fatalf("invalid route acquired canonical identity: %#v", route)
+			}
+			var quiet bytes.Buffer
+			got := app.Execute(context.Background(), append(append([]string(nil), path...), "-q", "--unknown"), Streams{Err: &quiet})
+			if got.Kind != OutcomeUsage || !strings.Contains(quiet.String(), "ERROR: unknown flag") || strings.Contains(quiet.String(), "DEBUG:") {
+				t.Fatalf("quiet alias outcome=%#v diagnostics=%q", got, quiet.String())
+			}
+		})
+	}
+	var scoped bytes.Buffer
+	got := app.Execute(context.Background(), []string{"group", "nested", "missing", "-x"}, Streams{Err: &scoped})
+	if got.Kind != OutcomeUsage || !strings.Contains(scoped.String(), "DEBUG:") {
+		t.Fatalf("scoped precedence outcome=%#v diagnostics=%q", got, scoped.String())
+	}
+	if calls != 0 {
+		t.Fatalf("invalid routes ran factories or handlers %d times", calls)
+	}
+}
+
 type executeReportingFailureWriter struct{ err error }
 
 func (w executeReportingFailureWriter) Write([]byte) (int, error) { return 0, w.err }