Allow ignoring specified environment variables

Add `[env] / ignore_keys` configuration to ignore the listed environment
variables, in addition to the default ones.

Fixes direnv#401

internal/cmd/config.go

@@ -29,6 +29,7 @@ type Config struct {
 	WarnTimeout     time.Duration
 	WhitelistPrefix []string
 	WhitelistExact  map[string]bool
+	EnvIgnoreKeys   []string
 }
 
 type tomlDuration struct {
@@ -45,6 +46,7 @@ type tomlConfig struct {
 	*tomlGlobal               // For backward-compatibility
 	Global      *tomlGlobal   `toml:"global"`
 	Whitelist   tomlWhitelist `toml:"whitelist"`
+	Env         tomlEnv       `toml:"env"`
 }
 
 type tomlGlobal struct {
@@ -60,6 +62,10 @@ type tomlWhitelist struct {
 	Exact  []string
 }
 
+type tomlEnv struct {
+	IgnoreKeys []string `toml:"ignore_keys"`
+}
+
 // LoadConfig opens up the direnv configuration from the Env.
 func LoadConfig(env Env) (config *Config, err error) {
 	config = &Config{
@@ -94,6 +100,8 @@ func LoadConfig(env Env) (config *Config, err error) {
 	config.WhitelistPrefix = make([]string, 0)
 	config.WhitelistExact = make(map[string]bool)
 
+	config.EnvIgnoreKeys = make([]string, 0)
+
 	// Load the TOML config
 	config.TomlPath = filepath.Join(config.ConfDir, "direnv.toml")
 	if _, statErr := os.Stat(config.TomlPath); statErr != nil {
@@ -118,6 +126,12 @@ func LoadConfig(env Env) (config *Config, err error) {
 			return
 		}
 
+		if env[DIRENV_IGNORE_KEYS] != "" {
+			config.EnvIgnoreKeys = strings.Split(env[DIRENV_IGNORE_KEYS], ",")
+		} else {
+			config.EnvIgnoreKeys = append(config.EnvIgnoreKeys, tomlConf.Env.IgnoreKeys...)
+		}
+
 		config.WhitelistPrefix = append(config.WhitelistPrefix, tomlConf.Whitelist.Prefix...)
 
 		for _, path := range tomlConf.Whitelist.Exact {

internal/cmd/const.go

@@ -12,4 +12,6 @@ const (
 	DIRENV_DIFF    = "DIRENV_DIFF"
 
 	DIRENV_DUMP_FILE_PATH = "DIRENV_DUMP_FILE_PATH"
+
+	DIRENV_IGNORE_KEYS = "DIRENV_IGNORE_KEYS"
 )

internal/cmd/env.go

@@ -41,6 +41,7 @@ func (env Env) CleanContext() {
 	delete(env, DIRENV_FILE)
 	delete(env, DIRENV_DUMP_FILE_PATH)
 	delete(env, DIRENV_WATCHES)
+	delete(env, DIRENV_IGNORE_KEYS)
 }
 
 // LoadEnv unmarshals the env back from a gzenv string

internal/cmd/env_diff.go

@@ -6,11 +6,12 @@ import (
 	"github.com/direnv/direnv/v2/gzenv"
 )
 
-// IgnoredKeys is list of keys we don't want to deal with
-var IgnoredKeys = map[string]bool{
+// DefaultIgnoredKeys is list of keys we don't want to deal with
+var DefaultIgnoredKeys = map[string]bool{
 	// direnv env config
-	"DIRENV_CONFIG": true,
-	"DIRENV_BASH":   true,
+	"DIRENV_CONFIG":      true,
+	"DIRENV_BASH":        true,
+	"DIRENV_IGNORE_KEYS": true,
 
 	// should only be available inside of the .envrc or .env
 	"DIRENV_IN_ENVRC": true,
@@ -27,6 +28,11 @@ var IgnoredKeys = map[string]bool{
 	"_":         true,
 }
 
+// IgnoredKeys represents all the keys we don't want to deal with
+type IgnoredKeys struct {
+	keys map[string]bool
+}
+
 // EnvDiff represents the diff between two environments
 type EnvDiff struct {
 	Prev map[string]string `json:"p"`
@@ -43,13 +49,15 @@ func NewEnvDiff() *EnvDiff {
 func BuildEnvDiff(e1, e2 Env) *EnvDiff {
 	diff := NewEnvDiff()
 
+	ignoredKeys := NewIgnoredKeys(e2)
+
 	in := func(key string, e Env) bool {
 		_, ok := e[key]
 		return ok
 	}
 
 	for key := range e1 {
-		if IgnoredEnv(key) {
+		if ignoredKeys.IsIgnored(key) {
 			continue
 		}
 		if e2[key] != e1[key] || !in(key, e2) {
@@ -58,7 +66,7 @@ func BuildEnvDiff(e1, e2 Env) *EnvDiff {
 	}
 
 	for key := range e2 {
-		if IgnoredEnv(key) {
+		if ignoredKeys.IsIgnored(key) {
 			continue
 		}
 		if e2[key] != e1[key] || !in(key, e1) {
@@ -131,16 +139,29 @@ func (diff *EnvDiff) Serialize() string {
 	return gzenv.Marshal(diff)
 }
 
-//// Utils
+//// IgnoredKeys
+
+// NewIgnoredKeys creates a NewIgnoredKeys including all keys to ignore
+func NewIgnoredKeys(env Env) *IgnoredKeys {
+	ignoredKeys := make(map[string]bool)
+
+	for key, value := range DefaultIgnoredKeys {
+		ignoredKeys[key] = value
+	}
+	for _, key := range strings.Split(env[DIRENV_IGNORE_KEYS], ",") {
+		ignoredKeys[key] = true
+	}
+	return &IgnoredKeys{ignoredKeys}
+}
 
-// IgnoredEnv returns true if the key should be ignored in environment diffs.
-func IgnoredEnv(key string) bool {
+// IsIgnored returns true if the key should be ignored in environment diffs.
+func (ignoredKeys *IgnoredKeys) IsIgnored(key string) bool {
 	if strings.HasPrefix(key, "__fish") {
 		return true
 	}
 	if strings.HasPrefix(key, "BASH_FUNC_") {
 		return true
 	}
-	_, found := IgnoredKeys[key]
+	_, found := ignoredKeys.keys[key]
 	return found
 }

internal/cmd/env_diff_test.go

@@ -37,20 +37,33 @@ func TestEnvDiffEmptyValue(t *testing.T) {
 	}
 }
 
-func TestIgnoredEnv(t *testing.T) {
-	if !IgnoredEnv(DIRENV_BASH) {
+func TestIgnoredKeysv(t *testing.T) {
+	env := Env{"DIRENV_IGNORE_KEYS": "FOO,BAR"}
+	ignoredKeys := NewIgnoredKeys(env)
+
+	if !ignoredKeys.IsIgnored(DIRENV_BASH) {
+		t.Fail()
+	}
+	if ignoredKeys.IsIgnored(DIRENV_DIFF) {
+		t.Fail()
+	}
+	if !ignoredKeys.IsIgnored("_") {
+		t.Fail()
+	}
+	if !ignoredKeys.IsIgnored("__fish_foo") {
 		t.Fail()
 	}
-	if IgnoredEnv(DIRENV_DIFF) {
+	if !ignoredKeys.IsIgnored("__fishx") {
 		t.Fail()
 	}
-	if !IgnoredEnv("_") {
+	if !ignoredKeys.IsIgnored("FOO") {
 		t.Fail()
 	}
-	if !IgnoredEnv("__fish_foo") {
+	if !ignoredKeys.IsIgnored("BAR") {
 		t.Fail()
 	}
-	if !IgnoredEnv("__fishx") {
+
+	if ignoredKeys.IsIgnored("BAZ") {
 		t.Fail()
 	}
 }

internal/cmd/rc.go

@@ -139,6 +139,7 @@ func (rc *RC) Load(previousEnv Env) (newEnv Env, err error) {
 	direnv := config.SelfPath
 	newEnv = previousEnv.Copy()
 	newEnv[DIRENV_WATCHES] = rc.times.Marshal()
+	newEnv[DIRENV_IGNORE_KEYS] = strings.Join(config.EnvIgnoreKeys, ",")
 	defer func() {
 		// Record directory changes even if load is disallowed or fails
 		newEnv[DIRENV_DIR] = "-" + filepath.Dir(rc.path)

man/direnv.toml.1

@@ -158,6 +158,24 @@ In this example, the following .envrc files will not be implicitly allowed (alth
 
 .RE
 
+.SH [env]
+.SS \fB\fCignore_keys\fR
+.PP
+List of environment variable names which should be ignored, in addition to some default ones.
+
+.PP
+Example:
+
+.PP
+.RS
+
+.nf
+[env]
+ignore_keys = ["TMUX_PANE", "SSH_AUTH_SOCK"]
+
+.fi
+.RE
+
 .SH COPYRIGHT
 .PP
 MIT licence - Copyright (C) 2019 @zimbatm and contributors

man/direnv.toml.1.md

@@ -109,6 +109,19 @@ In this example, the following .envrc files will not be implicitly allowed (alth
 * `/home/user/code/project-b/subproject-c/.envrc`
 * `/home/user/code/.envrc`
 
+## [env]
+
+### `ignore_keys`
+
+List of environment variable names which should be ignored, in addition to some default ones.
+
+Example:
+
+```toml
+[env]
+ignore_keys = ["TMUX_PANE", "SSH_AUTH_SOCK"]
+```
+
 COPYRIGHT
 ---------