wip: some more drastic refactoring

options.go

@@ -0,0 +1,80 @@
+package golden
+
+import "os"
+
+type Option interface {
+	apply(*gold)
+}
+
+type optionFunc func(*gold)
+
+func (fn optionFunc) apply(g *gold) {
+	fn(g)
+}
+
+// WithDirMode sets the file system permissions used for any folders created to
+// hold golden files.
+//
+// When this option is not provided, the default value is 0o755.
+func WithDirMode(mode os.FileMode) Option {
+	return optionFunc(func(g *gold) {
+		g.dirMode = mode
+	})
+}
+
+// WithFileMode sets the file system permissions used for any created or updated
+// golden files written to.
+//
+// When this option is not provided, the default value is 0o644.
+func WithFileMode(mode os.FileMode) Option {
+	return optionFunc(func(g *gold) {
+		g.fileMode = mode
+	})
+}
+
+// WithSuffix sets the filename suffix used for all golden files.
+//
+// When this option is not provided, the default value is ".golden".
+func WithSuffix(suffix string) Option {
+	return optionFunc(func(g *gold) {
+		g.suffix = suffix
+	})
+}
+
+// WithDirname sets the name of the top-level directory used to hold golden
+// files.
+//
+// When this option is not provided, the default value is "testdata".
+func WithDirname(name string) Option {
+	return optionFunc(func(g *gold) {
+		g.dirname = name
+	})
+}
+
+// WithUpdateFunc sets the function used to determine if golden files should be
+// updated or not. Essentially the provided UpdateFunc is called by Update().
+//
+// When this option is not provided, the default value is EnvUpdateFunc.
+func WithUpdateFunc(fn UpdateFunc) Option {
+	return optionFunc(func(g *gold) {
+		g.updateFunc = fn
+	})
+}
+
+// WithFS sets the afero.Fs instance which is used for all file system
+// operations to read/write golden files.
+//
+// When this option is not provided, the default value is afero.NewOsFs().
+func WithFS(fs FS) Option {
+	return optionFunc(func(g *gold) {
+		g.fs = fs
+	})
+}
+
+// WithSilentWrites silences the "golden: writing [...]" log messages whenever
+// set functions write a golden file to disk.
+func WithSilentWrites() Option {
+	return optionFunc(func(g *gold) {
+		g.logOnWrite = false
+	})
+}