test added to validate the changes of zshrc fix

Author: prathameshzarkar9

src/common-utils/main.sh

@@ -551,9 +551,7 @@ if [ "${INSTALL_ZSH}" = "true" ]; then
 
         # Add devcontainer .zshrc template
         if [ "$INSTALL_OH_MY_ZSH_CONFIG" = "true" ]; then
-            if [ -f "${template_path}" ] && grep -qF "$(head -n 1 "${template_path}")" "${user_rc_file}"; then
-                echo "No need to overwrite existing .zshrc file with the template file."
-            else
+            if ! [ -f "${template_path}" ] || ! grep -qF "$(head -n 1 "${template_path}")" "${user_rc_file}"; then
                 echo -e "$(cat "${template_path}")\nDISABLE_AUTO_UPDATE=true\nDISABLE_UPDATE_PROMPT=true" > ${user_rc_file}
             fi
             sed -i -e 's/ZSH_THEME=.*/ZSH_THEME="devcontainers"/g' ${user_rc_file}

test/common-utils/devcontainer-ruby-zshrc.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+set -e
+
+# Optional: Import test library
+source dev-container-features-test-lib
+
+# Definition specific tests
+check "configure-zshrc-without-overwrite" bash -c "grep 'rbenv init -' ~/.zshrc"
+
+# Report result
+reportResults

test/common-utils/devcontainer-ruby-zshrc/Dockerfile

@@ -0,0 +1,4 @@
+FROM mcr.microsoft.com/devcontainers/ruby:3.2
+
+RUN echo 'eval "$(rbenv init -)"' >> /home/vscode/.zshrc
+

test/common-utils/scenarios.json

@@ -235,6 +235,24 @@
             }
         }
     },
+    "devcontainer-ruby-zshrc": {
+        "build": {
+            "dockerfile": "Dockerfile"
+        },
+        "remoteUser": "vscode",
+        "features": {
+            "common-utils": {
+                "installZsh": true,
+                "username": "vscode",
+                "userUid": "1000",
+                "userGid": "1000",
+                "upgradePackages": true,
+                "installOhMyZsh": true,
+                "installOhMyZshConfig": true,
+                "configureZshAsDefaultShell": true
+            }
+        }
+    },
     "alpine-base-zsh-default": {
         "image": "mcr.microsoft.com/devcontainers/base:alpine",
         "remoteUser": "vscode",