config updated to improve setting values, writing changes and test coverage

internal/config/conf_sections_test.go

@@ -455,3 +455,70 @@ func TestLoadFromViperInvalidValues(t *testing.T) {
 		}
 	}
 }
+
+func TestDatabaseSection(t *testing.T) {
+	c := JobSearchConfigDatabase{File: "./jobsearch.db"}
+
+	if got, want := c.Keys(), []string{"file"}; !reflect.DeepEqual(got, want) {
+		t.Errorf("Keys = %v; want %v", got, want)
+	}
+	if got, want := c.Map(), map[string]any{"file": "./jobsearch.db"}; !reflect.DeepEqual(got, want) {
+		t.Errorf("Map = %v; want %v", got, want)
+	}
+	want := map[string]any{"database.file": "./jobsearch.db"}
+	if got := c.Flatten(); !reflect.DeepEqual(got, want) {
+		t.Errorf("Flatten = %v; want %v", got, want)
+	}
+	if k, err := c.TypeOf("file"); err != nil || k != reflect.String {
+		t.Errorf("TypeOf(file) = %v, %v", k, err)
+	}
+	if v, err := c.ValueOf("file"); err != nil || v != "./jobsearch.db" {
+		t.Errorf("ValueOf(file) = %v, %v", v, err)
+	}
+	if _, err := c.TypeOf("nope"); err == nil {
+		t.Error("TypeOf(nope) succeeded")
+	}
+	if _, err := c.ValueOf("nope"); err == nil {
+		t.Error("ValueOf(nope) succeeded")
+	}
+	if err := c.SetValue("file", "/var/lib/js.db"); err != nil || c.File != "/var/lib/js.db" {
+		t.Errorf("SetValue(file) = %v, File = %q", err, c.File)
+	}
+	if err := c.SetValue("file", 42); err == nil {
+		t.Error("SetValue(file, 42) succeeded")
+	}
+
+	// The root configuration reaches it as database.file.
+	conf := defaultConfig(t)
+	if err := conf.SetValue("database.file", "./other.db"); err != nil ||
+		conf.Database.File != "./other.db" {
+		t.Errorf("SetValue(database.file) = %v, File = %q", err, conf.Database.File)
+	}
+}
+
+func TestViperValue(t *testing.T) {
+	resetViper(t)
+	viper.Set("s", "text")
+	viper.Set("i", "42") // strings are converted
+	viper.Set("b", "true")
+
+	for _, tt := range []struct {
+		key  string
+		kind reflect.Kind
+		want any
+	}{
+		{"s", reflect.String, "text"},
+		{"i", reflect.Int, 42},
+		{"b", reflect.Bool, true},
+	} {
+		got, ok := viperValue(tt.key, tt.kind)
+		if !ok || got != tt.want {
+			t.Errorf("viperValue(%q, %v) = %#v, %v; want %#v", tt.key, tt.kind, got, ok, tt.want)
+		}
+	}
+	for _, kind := range []reflect.Kind{reflect.Float64, reflect.Int8, reflect.Slice} {
+		if got, ok := viperValue("i", kind); ok {
+			t.Errorf("viperValue(i, %v) = %#v, true; want unhandled", kind, got)
+		}
+	}
+}