add the devcontainer prompt

Author: gilesknap

.devcontainer/features/bash-config/config/bash-config-rc

@@ -11,4 +11,29 @@ export HISTSIZE=-1
 export HISTFILESIZE=-1
 export SAVEHIST=-1
 export HISTFILE=$CONFIG_FOLDER/.bash_eternal_history
-PROMPT_COMMAND="history -a; $PROMPT_COMMAND"
+
+# bash theme - partly inspired by https://github.com/ohmyzsh/ohmyzsh/blob/master/themes/robbyrussell.zsh-theme
+# from https://github.com/devcontainers/features/blob/main/src/common-utils/scripts/bash_theme_snippet.sh
+__bash_prompt() {
+    local userpart='`export XIT=$? \
+        && [ ! -z "${GITHUB_USER:-}" ] && echo -n "\[\033[0;32m\]@${GITHUB_USER:-} " || echo -n "\[\033[0;32m\]\u " \
+        && [ "$XIT" -ne "0" ] && echo -n "\[\033[1;31m\]➜" || echo -n "\[\033[0m\]➜"`'
+    local gitbranch='`\
+        if [ "$(git config --get devcontainers-theme.hide-status 2>/dev/null)" != 1 ] && [ "$(git config --get codespaces-theme.hide-status 2>/dev/null)" != 1 ]; then \
+            export BRANCH="$(git --no-optional-locks symbolic-ref --short HEAD 2>/dev/null || git --no-optional-locks rev-parse --short HEAD 2>/dev/null)"; \
+            if [ "${BRANCH:-}" != "" ]; then \
+                echo -n "\[\033[0;36m\](\[\033[1;31m\]${BRANCH:-}" \
+                && if [ "$(git config --get devcontainers-theme.show-dirty 2>/dev/null)" = 1 ] && \
+                    git --no-optional-locks ls-files --error-unmatch -m --directory --no-empty-directory -o --exclude-standard ":/*" > /dev/null 2>&1; then \
+                        echo -n " \[\033[1;33m\]✗"; \
+                fi \
+                && echo -n "\[\033[0;36m\]) "; \
+            fi; \
+        fi`'
+    local lightblue='\[\033[1;34m\]'
+    local removecolor='\[\033[0m\]'
+    PS1="${userpart} ${lightblue}\w ${gitbranch}${removecolor}\$ "
+    unset -f __bash_prompt
+}
+__bash_prompt
+export PROMPT_DIRTRIM=4