From d90625dc0a91844c0f09861ec88a2fa30bae63e3 Mon Sep 17 00:00:00 2001
From: Alexander Wang <alex@terrastruct.com>
Date: Wed, 16 Nov 2022 16:55:12 -0800
Subject: [PATCH] 2022-11-16 04:55:12PM

---
 ci/release/changelogs/next.md |  3 ++-
 lib/xmain/opts.go             | 49 ++++++++++++++++-------------------
 2 files changed, 25 insertions(+), 27 deletions(-)

diff --git a/ci/release/changelogs/next.md b/ci/release/changelogs/next.md
index ffd49ca9c..abd4b28f7 100644
--- a/ci/release/changelogs/next.md
+++ b/ci/release/changelogs/next.md
@@ -6,7 +6,8 @@ For v0.0.99 we focused on X, Y and Z. Enjoy!
 
 #### Improvements 🔧
 
-- Add table columns indices in edges between SQL Tables so that layout engines can route exactly between them
+- Equivalency between flags and environment variables. You can set either one for all
+  options (flags take precedence).
 
 #### Bugfixes 🔴
 
diff --git a/lib/xmain/opts.go b/lib/xmain/opts.go
index 498f0db7e..ed260537f 100644
--- a/lib/xmain/opts.go
+++ b/lib/xmain/opts.go
@@ -52,47 +52,44 @@ func (o *Opts) Help() string {
 	return b.String()
 }
 
+func (o *Opts) getEnv(k string) string {
+	if k != "" {
+		o.registeredEnvs = append(o.registeredEnvs, k)
+		return o.env.Getenv(k)
+	}
+	return ""
+}
+
 func (o *Opts) Int64(envKey, flag, shortFlag string, defaultVal int64, usage string) (*int64, error) {
-	if envKey != "" {
-		if o.env.Getenv(envKey) != "" {
-			envVal, err := strconv.ParseInt(o.env.Getenv(envKey), 10, 64)
-			if err != nil {
-				return nil, fmt.Errorf(`invalid environment variable %s. Expected int64. Found "%v".`, envKey, envVal)
-			}
-			defaultVal = envVal
+	if env := o.getEnv(envKey); env != "" {
+		envVal, err := strconv.ParseInt(env, 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf(`invalid environment variable %s. Expected int64. Found "%v".`, envKey, envVal)
 		}
-		o.registeredEnvs = append(o.registeredEnvs, envKey)
+		defaultVal = envVal
 	}
 
 	return o.Flags.Int64P(flag, shortFlag, defaultVal, usage), nil
 }
 
 func (o *Opts) String(envKey, flag, shortFlag string, defaultVal, usage string) *string {
-	if envKey != "" {
-		if o.env.Getenv(envKey) != "" {
-			envVal := o.env.Getenv(envKey)
-			defaultVal = envVal
-		}
-		o.registeredEnvs = append(o.registeredEnvs, envKey)
+	if env := o.getEnv(envKey); env != "" {
+		defaultVal = env
 	}
 
 	return o.Flags.StringP(flag, shortFlag, defaultVal, usage)
 }
 
 func (o *Opts) Bool(envKey, flag, shortFlag string, defaultVal bool, usage string) (*bool, error) {
-	if envKey != "" {
-		if o.env.Getenv(envKey) != "" {
-			envVal := o.env.Getenv(envKey)
-			if !boolyEnv(envVal) {
-				return nil, fmt.Errorf(`invalid environment variable %s. Expected bool. Found "%s".`, envKey, envVal)
-			}
-			if truthyEnv(envVal) {
-				defaultVal = true
-			} else {
-				defaultVal = false
-			}
+	if env := o.getEnv(envKey); env != "" {
+		if !boolyEnv(env) {
+			return nil, fmt.Errorf(`invalid environment variable %s. Expected bool. Found "%s".`, envKey, env)
+		}
+		if truthyEnv(env) {
+			defaultVal = true
+		} else {
+			defaultVal = false
 		}
-		o.registeredEnvs = append(o.registeredEnvs, envKey)
 	}
 
 	return o.Flags.BoolP(flag, shortFlag, defaultVal, usage), nil