From cbc7aae19e321f0fb5993a0e69988e3eecc00597 Mon Sep 17 00:00:00 2001
From: Day <daychongyang@gmail.com>
Date: Sun, 4 Dec 2022 07:28:23 +0800
Subject: [PATCH] refactor: os.LookupEnv (#2708)

---
 cmd/esbuild/main.go       |  7 ++-----
 internal/logger/logger.go | 17 ++++++-----------
 pkg/api/api_impl.go       |  4 ++--
 pkg/cli/cli_impl.go       | 24 ++++++++++--------------
 4 files changed, 20 insertions(+), 32 deletions(-)

diff --git a/cmd/esbuild/main.go b/cmd/esbuild/main.go
index 1208cb916d5..76712ccc8f6 100644
--- a/cmd/esbuild/main.go
+++ b/cmd/esbuild/main.go
@@ -16,11 +16,8 @@ import (
 var helpText = func(colors logger.Colors) string {
 	// Read "NO_COLOR" from the environment. This is a convention that some
 	// software follows. See https://no-color.org/ for more information.
-	for _, key := range os.Environ() {
-		if strings.HasPrefix(key, "NO_COLOR=") {
-			colors = logger.Colors{}
-			break
-		}
+	if _, ok := os.LookupEnv("NO_COLOR"); ok {
+		colors = logger.Colors{}
 	}
 
 	return `
diff --git a/internal/logger/logger.go b/internal/logger/logger.go
index 2121e8424f9..de3fb0b800b 100644
--- a/internal/logger/logger.go
+++ b/internal/logger/logger.go
@@ -133,11 +133,8 @@ func isProbablyWindowsCommandPrompt() bool {
 		// because that means we're running in the new Windows Terminal instead.
 		if runtime.GOOS == "windows" {
 			windowsCommandPrompt.isProbablyCMD = true
-			for _, env := range os.Environ() {
-				if strings.HasPrefix(env, "WT_SESSION=") {
-					windowsCommandPrompt.isProbablyCMD = false
-					break
-				}
+			if _, ok := os.LookupEnv("WT_SESSION"); ok {
+				windowsCommandPrompt.isProbablyCMD = false
 			}
 		}
 	}
@@ -261,12 +258,10 @@ var noColorOnce sync.Once
 
 func hasNoColorEnvironmentVariable() bool {
 	noColorOnce.Do(func() {
-		for _, key := range os.Environ() {
-			// Read "NO_COLOR" from the environment. This is a convention that some
-			// software follows. See https://no-color.org/ for more information.
-			if strings.HasPrefix(key, "NO_COLOR=") {
-				noColorResult = true
-			}
+		// Read "NO_COLOR" from the environment. This is a convention that some
+		// software follows. See https://no-color.org/ for more information.
+		if _, ok := os.LookupEnv("NO_COLOR"); ok {
+			noColorResult = true
 		}
 	})
 	return noColorResult
diff --git a/pkg/api/api_impl.go b/pkg/api/api_impl.go
index ddab0528c17..4f90e89e7c4 100644
--- a/pkg/api/api_impl.go
+++ b/pkg/api/api_impl.go
@@ -921,8 +921,8 @@ func printSummary(logOptions logger.OutputOptions, outputFiles []OutputFile, sta
 
 	// Don't print the time taken by the build if we're running under Yarn 1
 	// since Yarn 1 always prints its own copy of the time taken by each command
-	for _, env := range os.Environ() {
-		if strings.HasPrefix(env, "npm_config_user_agent=") && strings.Contains(env, "yarn/1.") {
+	if userAgent, ok := os.LookupEnv("npm_config_user_agent"); ok {
+		if strings.Contains(userAgent, "yarn/1.") {
 			logger.PrintSummary(logOptions.Color, table, nil)
 			return
 		}
diff --git a/pkg/cli/cli_impl.go b/pkg/cli/cli_impl.go
index add61da1271..75091f88c99 100644
--- a/pkg/cli/cli_impl.go
+++ b/pkg/cli/cli_impl.go
@@ -1064,20 +1064,16 @@ func runImpl(osArgs []string) int {
 
 	switch {
 	case buildOptions != nil:
-		for _, key := range os.Environ() {
-			// Read the "NODE_PATH" from the environment. This is part of node's
-			// module resolution algorithm. Documentation for this can be found here:
-			// https://nodejs.org/api/modules.html#modules_loading_from_the_global_folders
-			if strings.HasPrefix(key, "NODE_PATH=") {
-				value := key[len("NODE_PATH="):]
-				separator := ":"
-				if fs.CheckIfWindows() {
-					// On Windows, NODE_PATH is delimited by semicolons instead of colons
-					separator = ";"
-				}
-				buildOptions.NodePaths = splitWithEmptyCheck(value, separator)
-				break
-			}
+		// Read the "NODE_PATH" from the environment. This is part of node's
+		// module resolution algorithm. Documentation for this can be found here:
+		// https://nodejs.org/api/modules.html#modules_loading_from_the_global_folders
+		if value, ok := os.LookupEnv("NODE_PATH"); ok {
+			separator := ":"
+			if fs.CheckIfWindows() {
+				// On Windows, NODE_PATH is delimited by semicolons instead of colons
+				separator = ";"
+			}
+			buildOptions.NodePaths = splitWithEmptyCheck(value, separator)
 		}
 
 		// Read from stdin when there are no entry points