Add custom bash PS1

Referenced <https://stackoverflow.com/a/11975827> to get git tag names.

.bashrc

@@ -86,6 +86,46 @@ xterm*|rxvt*)
     ;;
 esac
 
+function we_are_in_git_work_tree {
+    git rev-parse --is-inside-work-tree &> /dev/null
+}
+
+function parse_git_branch {
+    if we_are_in_git_work_tree
+    then
+        local BR=$(git rev-parse --symbolic-full-name --abbrev-ref HEAD 2> /dev/null)
+        if [ "$BR" == HEAD ]
+        then
+            # revision isn't a named branch, try to get tag name
+            local NM=$(git name-rev --name-only HEAD 2> /dev/null)
+            # revision isn't a tag, use shortened hash
+            if [ "$NM" != undefined ]
+            then echo -n "@$NM"
+            else git rev-parse --short HEAD 2> /dev/null
+            fi
+        else
+            echo -n $BR
+        fi
+    fi
+}
+
+function set_prompt {
+    # local time="\[\e[34m\]\T\[\e[m\]-"
+    local user="\[\e[36m\]\u"
+    local at="\[\e[m\]@"
+    local host="\[\e[32m\]`hostname | cut -d "-" -f 3`\[\e[m\]:"
+    local dir="\[\e[33m\]\w"
+    local git_color="\[\033[31m\]"
+    local git_branch='(`parse_git_branch`)'
+    local git_diff='`git rev-parse 2>/dev/null && (git diff --no-ext-diff --quiet --exit-code 2> /dev/null || echo -e \*)`'
+    local prompt="\[\e[m\]$"
+
+    # export PS1="$time$user$at$host$dir$git_color$git_branch$git_diff$prompt "
+    export PS1="$user$at$host$dir$git_color$git_branch$git_diff$prompt "
+}
+
+set_prompt
+
 # enable color support of ls and also add handy aliases
 if [ -x /usr/bin/dircolors ]; then
     test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"

README.md

@@ -36,7 +36,9 @@ New machine:
     * <https://old.reddit.com/r/tmux/comments/yd62te/i_really_need_help_with_italic_and_truecolor>
 
 * fix git gutter / fugitive not working for bare repo
-    * potential leads:
+    * workaround is to invoke nvim after setting some env vars:
+        `GIT_DIR=$HOME/.dotfiles GIT_WORK_TREE=$HOME nvim`
+    * similar problem discussed here:
       * <https://github.com/tpope/vim-fugitive/issues/1981#issuecomment-1107388377>
       * <https://stackoverflow.com/a/66624354/5323947>