feat: add a quiet flag to suppress all output except for errors

Signed-off-by: Brian McGee <brian@bmcgee.ie>

diff --git a/cmd/root.go b/cmd/root.go
index 72348f1..cd3f8f7 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -144,13 +144,19 @@ func runE(v *viper.Viper, statz *stats.Stats, cmd *cobra.Command, args []string)
 	log.SetOutput(os.Stderr)
 	log.SetReportTimestamp(false)

-	switch v.GetInt("verbose") {
-	case 0:
-		log.SetLevel(log.WarnLevel)
-	case 1:
-		log.SetLevel(log.InfoLevel)
-	default:
-		log.SetLevel(log.DebugLevel)
+	if v.GetBool("quiet") {
+		// if quiet, we only log errors
+		log.SetLevel(log.ErrorLevel)
+	} else {
+		// otherwise, the verbose flag controls the log level
+		switch v.GetInt("verbose") {
+		case 0:
+			log.SetLevel(log.WarnLevel)
+		case 1:
+			log.SetLevel(log.InfoLevel)
+		default:
+			log.SetLevel(log.DebugLevel)
+		}
 	}

 	// format
diff --git a/cmd/root_test.go b/cmd/root_test.go
index 2846504..628a69b 100644
--- a/cmd/root_test.go
+++ b/cmd/root_test.go
@@ -131,6 +131,33 @@ func TestOnUnmatched(t *testing.T) {
 	})
 }

+func TestQuiet(t *testing.T) {
+	as := require.New(t)
+	tempDir := test.TempExamples(t)
+
+	test.ChangeWorkDir(t, tempDir)
+
+	// allow missing formatter
+	t.Setenv("TREEFMT_ALLOW_MISSING_FORMATTER", "true")
+
+	noOutput := func(out []byte) {
+		as.Empty(out)
+	}
+
+	treefmt(t, withArgs("-q"), withNoError(t), withStdout(noOutput), withStderr(noOutput))
+	treefmt(t, withArgs("--quiet"), withNoError(t), withStdout(noOutput), withStderr(noOutput))
+
+	t.Setenv("TREEFMT_QUIET", "true")
+	treefmt(t, withNoError(t), withStdout(noOutput), withStderr(noOutput))
+
+	t.Setenv("TREEFMT_ALLOW_MISSING_FORMATTER", "false")
+
+	// check it doesn't suppress errors
+	treefmt(t, withError(func(err error) {
+		as.ErrorContains(err, "error looking up 'foo-fmt'")
+	}))
+}
+
 func TestCpuProfile(t *testing.T) {
 	as := require.New(t)
 	tempDir := test.TempExamples(t)
diff --git a/config/config.go b/config/config.go
index f5d8e7a..c10df3f 100644
--- a/config/config.go
+++ b/config/config.go
@@ -22,6 +22,7 @@ type Config struct {
 	Formatters            []string `mapstructure:"formatters"              toml:"formatters,omitempty"`
 	NoCache               bool     `mapstructure:"no-cache"                toml:"-"` // not allowed in config
 	OnUnmatched           string   `mapstructure:"on-unmatched"            toml:"on-unmatched,omitempty"`
+	Quiet                 bool     `mapstructure:"quiet"                   toml:"-"` // not allowed in config
 	TreeRoot              string   `mapstructure:"tree-root"               toml:"tree-root,omitempty"`
 	TreeRootFile          string   `mapstructure:"tree-root-file"          toml:"tree-root-file,omitempty"`
 	Verbose               uint8    `mapstructure:"verbose"                 toml:"verbose,omitempty"`
@@ -110,6 +111,9 @@ func SetFlags(fs *pflag.FlagSet) {
 		"verbose", "v",
 		"Set the verbosity of logs e.g. -vv. (env $TREEFMT_VERBOSE)",
 	)
+	fs.BoolP(
+		"quiet", "q", false, "Disable all logs except errors. (env $TREEFMT_QUIET)",
+	)
 	fs.String(
 		"walk", "auto",
 		"The method used to traverse the files within the tree root. Currently supports "+
diff --git a/config/config_test.go b/config/config_test.go
index 281e18a..ae6dc83 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -323,6 +323,36 @@ func TestNoCache(t *testing.T) {
 	checkValue(true)
 }

+func TestQuiet(t *testing.T) {
+	as := require.New(t)
+
+	cfg := &config.Config{}
+	v, flags := newViper(t)
+
+	checkValue := func(expected bool) {
+		readValue(t, v, cfg, func(cfg *config.Config) {
+			as.Equal(expected, cfg.Quiet)
+		})
+	}
+
+	// default with no flag, env or config
+	checkValue(false)
+
+	// set config value and check that it has no effect
+	// you are not allowed to set no-cache in config
+	cfg.Quiet = true
+
+	checkValue(false)
+
+	// env override
+	t.Setenv("TREEFMT_QUIET", "false")
+	checkValue(false)
+
+	// flag override
+	as.NoError(flags.Set("quiet", "true"))
+	checkValue(true)
+}
+
 func TestOnUnmatched(t *testing.T) {
 	as := require.New(t)

diff --git a/docs/content/getting-started/configure.md b/docs/content/getting-started/configure.md
index efc8f2b..623077e 100644
--- a/docs/content/getting-started/configure.md
+++ b/docs/content/getting-started/configure.md
@@ -254,6 +254,22 @@ Possible values are `<debug|info|warn|error|fatal>`.
     on-unmatched = "debug"
     ```

+### `quiet`
+
+Suppress all output except for errors.
+
+=== "Flag"
+
+    ```console
+    treefmt --quiet
+    ```
+
+=== "Env"
+
+    ```console
+    TREEFMT_QUIET=true treefmt
+    ```
+
 ### `stdin`

 Format the context passed in via stdin.

cmd/root.go

@@ -144,13 +144,19 @@ func runE(v *viper.Viper, statz *stats.Stats, cmd *cobra.Command, args []string)
 	log.SetOutput(os.Stderr)
 	log.SetReportTimestamp(false)
 
-	switch v.GetInt("verbose") {
-	case 0:
-		log.SetLevel(log.WarnLevel)
-	case 1:
-		log.SetLevel(log.InfoLevel)
-	default:
-		log.SetLevel(log.DebugLevel)
+	if v.GetBool("quiet") {
+		// if quiet, we only log errors
+		log.SetLevel(log.ErrorLevel)
+	} else {
+		// otherwise, the verbose flag controls the log level
+		switch v.GetInt("verbose") {
+		case 0:
+			log.SetLevel(log.WarnLevel)
+		case 1:
+			log.SetLevel(log.InfoLevel)
+		default:
+			log.SetLevel(log.DebugLevel)
+		}
 	}
 
 	// format

cmd/root_test.go

@@ -131,6 +131,33 @@ func TestOnUnmatched(t *testing.T) {
 	})
 }
 
+func TestQuiet(t *testing.T) {
+	as := require.New(t)
+	tempDir := test.TempExamples(t)
+
+	test.ChangeWorkDir(t, tempDir)
+
+	// allow missing formatter
+	t.Setenv("TREEFMT_ALLOW_MISSING_FORMATTER", "true")
+
+	noOutput := func(out []byte) {
+		as.Empty(out)
+	}
+
+	treefmt(t, withArgs("-q"), withNoError(t), withStdout(noOutput), withStderr(noOutput))
+	treefmt(t, withArgs("--quiet"), withNoError(t), withStdout(noOutput), withStderr(noOutput))
+
+	t.Setenv("TREEFMT_QUIET", "true")
+	treefmt(t, withNoError(t), withStdout(noOutput), withStderr(noOutput))
+
+	t.Setenv("TREEFMT_ALLOW_MISSING_FORMATTER", "false")
+
+	// check it doesn't suppress errors
+	treefmt(t, withError(func(err error) {
+		as.ErrorContains(err, "error looking up 'foo-fmt'")
+	}))
+}
+
 func TestCpuProfile(t *testing.T) {
 	as := require.New(t)
 	tempDir := test.TempExamples(t)

config/config.go

@@ -22,6 +22,7 @@ type Config struct {
 	Formatters            []string `mapstructure:"formatters"              toml:"formatters,omitempty"`
 	NoCache               bool     `mapstructure:"no-cache"                toml:"-"` // not allowed in config
 	OnUnmatched           string   `mapstructure:"on-unmatched"            toml:"on-unmatched,omitempty"`
+	Quiet                 bool     `mapstructure:"quiet"                   toml:"-"` // not allowed in config
 	TreeRoot              string   `mapstructure:"tree-root"               toml:"tree-root,omitempty"`
 	TreeRootFile          string   `mapstructure:"tree-root-file"          toml:"tree-root-file,omitempty"`
 	Verbose               uint8    `mapstructure:"verbose"                 toml:"verbose,omitempty"`
@@ -110,6 +111,9 @@ func SetFlags(fs *pflag.FlagSet) {
 		"verbose", "v",
 		"Set the verbosity of logs e.g. -vv. (env $TREEFMT_VERBOSE)",
 	)
+	fs.BoolP(
+		"quiet", "q", false, "Disable all logs except errors. (env $TREEFMT_QUIET)",
+	)
 	fs.String(
 		"walk", "auto",
 		"The method used to traverse the files within the tree root. Currently supports "+

config/config_test.go

@@ -323,6 +323,36 @@ func TestNoCache(t *testing.T) {
 	checkValue(true)
 }
 
+func TestQuiet(t *testing.T) {
+	as := require.New(t)
+
+	cfg := &config.Config{}
+	v, flags := newViper(t)
+
+	checkValue := func(expected bool) {
+		readValue(t, v, cfg, func(cfg *config.Config) {
+			as.Equal(expected, cfg.Quiet)
+		})
+	}
+
+	// default with no flag, env or config
+	checkValue(false)
+
+	// set config value and check that it has no effect
+	// you are not allowed to set no-cache in config
+	cfg.Quiet = true
+
+	checkValue(false)
+
+	// env override
+	t.Setenv("TREEFMT_QUIET", "false")
+	checkValue(false)
+
+	// flag override
+	as.NoError(flags.Set("quiet", "true"))
+	checkValue(true)
+}
+
 func TestOnUnmatched(t *testing.T) {
 	as := require.New(t)
 

docs/content/getting-started/configure.md

@@ -254,6 +254,22 @@ Possible values are `<debug|info|warn|error|fatal>`.
     on-unmatched = "debug"
     ```
 
+### `quiet`
+
+Suppress all output except for errors.
+
+=== "Flag"
+
+    ```console
+    treefmt --quiet
+    ```
+
+=== "Env"
+
+    ```console
+    TREEFMT_QUIET=true treefmt
+    ```
+
 ### `stdin`
 
 Format the context passed in via stdin.