support command output in prompt

docs/prompt.md

@@ -15,21 +15,33 @@ username@hostname: current-dir$
 ## Available Prompt items
 
 A prompt item is prompt value fields like `$USER`, `${COLOR_STATUS}` etc.
-Note `$XYZ` is the same as `${XYZ}`, but sometime you need the `${XYZ}` form
-to achieve prompt string like `FOO${XYZ}BAR`, where it would be treated as
-`$XYZBAR` without the `{}` chars. Also, `$XYZ` is the same as `$xyz`.
+Note `$XYZ` is the same as `${XYZ}`, and `$XYZ` is the same as `$xyz`.
 
 | Prompt Item | Description |
 | --- | --- |
-| ${BLUE} | change terminal color to blue. |
-| ${COLOR_STATUS} | change terminal color to green/red based on last exit status code. |
 | ${CWD} | current work directory base name. e.g. `baz` for dir `/foo/bar/baz`. |
-| ${GREEN} | change terminal color to green. |
 | ${HOSTNAME} | system hostname. |
 | ${NEWLINE} | the newline char: `\n`. |
-| ${RED} | change terminal color to red. |
-| ${RESET} | reset terminal color. |
 | ${USER} | system user name. |
+| ${BLACK} | change terminal color to black. |
+| ${BLACK_B} | change terminal color to bold black. |
+| ${BLACK_BG} | change terminal color to background black. |
+| ${BLUE} | change terminal color to blue. |
+| ${BLUE_B} | change terminal color to bold blue. |
+| ${BLUE_BG} | change terminal color to background blue. |
+| ${GREEN} | change terminal color to green. |
+| ${GREEN_B} | change terminal color to bold green. |
+| ${GREEN_BG} | change terminal color to background green. |
+| ${RED} | change terminal color to red. |
+| ${RED_B} | change terminal color to bold red. |
+| ${RED_BG} | change terminal color to background red. |
+| ${WHITE} | change terminal color to white. |
+| ${WHITE_B} | change terminal color to bold white. |
+| ${WHITE_BG} | change terminal color to background white. |
+| ${COLOR_STATUS} | change terminal color to green/red based on last exit status code. |
+| ${BOLD} | make text bold. |
+| ${UNDERLINED} | Underlined text. |
+| ${RESET} | reset terminal color & format. |
 
 Note you can also use regular environment variables that not in the list, like `$HOME`, in the `$PROMPT` value.
 
@@ -39,3 +51,25 @@ See also [builtin vox](https://github.com/mitnk/cicada/blob/master/docs/built-in
 
 When you enter a virtual env, the prompt will prefix by `(pyenv-name)`. e.g.
 `(evn-test)mitnk:mbp: pip$ `.
+
+## Use Command Output in Prompt
+
+You can use `$(the cmd line)` in prompt, and the output of command
+`the cmd line` will be rendered in prompt. e.g.
+```
+export PROMPT="[$(git rev-parse --abbrev-ref HEAD)] $USER@HOSTNAME$ "
+```
+would render prompt with:
+```
+$ [master] mitnk@mpb$
+```
+
+### Use prefix & suffix in it (BETA)
+You can use `[` or `{` as prefix, and `]`, `}` as suffix when using command
+output int prompt. e.g.
+```
+export PROMPT="$({git rev-parse --abbrev-ref HEAD}) $USER@HOSTNAME$ "
+```
+So that when the output of the command is empty, the prefix/suffix wouldn't
+be rendered either.
+

src/libs/colored.rs

@@ -1,6 +1,24 @@
 // setting prompt in crate linefeed needs wrap every SEQ chars
 // with prefixing with '\x01' and suffix with '\x02'.
+// todo full list - https://misc.flogisoft.com/bash/tip_colors_and_formatting
+pub const RESET: &str = "\x01\x1B[0m\x02";
+pub const BOLD: &str = "\x01\x1B[1m\x02";
+pub const UNDERLINED: &str = "\x01\x1B[4m\x02";
+
 pub const BLUE: &str = "\x01\x1B[34m\x02";
+pub const BLACK: &str = "\x01\x1B[30m\x02";
+pub const WHITE: &str = "\x01\x1B[97m\x02";
 pub const RED: &str = "\x01\x1B[31m\x02";
 pub const GREEN: &str = "\x01\x1B[32m\x02";
-pub const RESET: &str = "\x01\x1B[0m\x02";
+
+pub const BLUE_B: &str = "\x01\x1B[34m\x1B[1m\x02";
+pub const BLACK_B: &str = "\x01\x1B[30m\x1B[1m\x02";
+pub const WHITE_B: &str = "\x01\x1B[97m\x1B[1m\x02";
+pub const RED_B: &str = "\x01\x1B[31m\x1B[1m\x02";
+pub const GREEN_B: &str = "\x01\x1B[32m\x1B[1m\x02";
+
+pub const BLUE_BG: &str = "\x01\x1B[44m\x02";
+pub const BLACK_BG: &str = "\x01\x1B[40m\x02";
+pub const WHITE_BG: &str = "\x01\x1B[107m\x02";
+pub const RED_BG: &str = "\x01\x1B[41m\x02";
+pub const GREEN_BG: &str = "\x01\x1B[42m\x02";

src/prompt/main.rs

@@ -1,12 +1,21 @@
 use std::env;
 
+use execute;
 use shell;
 use tools;
 
 const DEFAULT_PROMPT: &str = "${COLOR_STATUS}$USER${RESET}@${COLOR_STATUS}$HOSTNAME${RESET}: ${COLOR_STATUS}$CWD${RESET}$ ";
-use super::preset::apply_preset_token;
+use super::preset::apply_preset_item;
 use super::preset::apply_pyenv;
 
+fn is_prefix_char(c: char) -> bool {
+    c == '[' || c == '{'
+}
+
+fn is_suffix_char(c: char) -> bool {
+    c == ']' || c == '}'
+}
+
 fn is_prompt_item_char(c: char) -> bool {
     let s = c.to_string();
     tools::re_contains(&s, r#"^[a-zA-Z_]$"#)
@@ -19,28 +28,57 @@ pub fn get_prompt_string() -> String {
     DEFAULT_PROMPT.to_string()
 }
 
-fn apply_token(sh: &shell::Shell, result: &mut String, token: &str) {
+fn apply_prompt_item(sh: &shell::Shell, result: &mut String, token: &str) {
     if let Ok(x) = env::var(token) {
         result.push_str(&x);
         return;
     }
-    apply_preset_token(sh, result, token);
+    apply_preset_item(sh, result, token);
+}
+
+fn apply_command(result: &mut String, token: &str, prefix: &str, suffix: &str) {
+    let cr = execute::run(&token);
+    let output = cr.stdout.trim();
+    if !output.is_empty() {
+        result.push_str(&prefix);
+        result.push_str(&output);
+        result.push_str(&suffix);
+    }
 }
 
 pub fn render_prompt(sh: &shell::Shell, ps: &str) -> String {
     let mut prompt = String::new();
     apply_pyenv(&mut prompt);
 
     let mut met_dollar = false;
+    let mut met_brace = false;
+    let mut met_paren = false;
     let mut token = String::new();
+    let mut prefix = String::new();
+    let mut suffix = String::new();
     for c in ps.chars() {
         if met_dollar {
-            if c == '{' {
+            if c == '(' && !met_brace && !met_paren {
+                met_paren = true;
+                continue;
+            }
+            if c == ')' && met_paren {
+                apply_command(&mut prompt, &token, &prefix, &suffix);
+                token.clear();
+                prefix.clear();
+                suffix.clear();
+                met_dollar = false;
+                met_paren = false;
+                continue;
+            }
+            if c == '{' && !met_brace && !met_paren {
+                met_brace = true;
                 continue;
-            } else if c == '}' {
-                apply_token(sh, &mut prompt, &token);
+            } else if c == '}' && met_brace {
+                apply_prompt_item(sh, &mut prompt, &token);
                 token.clear();
                 met_dollar = false;
+                met_brace = false;
                 continue;
             } else if c == '$' {
                 if token.is_empty() {
@@ -49,11 +87,20 @@ pub fn render_prompt(sh: &shell::Shell, ps: &str) -> String {
                     met_dollar = true;
                     continue;
                 } else {
-                    apply_token(sh, &mut prompt, &token);
+                    apply_prompt_item(sh, &mut prompt, &token);
                     token.clear();
                     // met_dollar is still true
                     continue;
                 }
+            } else if met_paren {
+                if is_prefix_char(c) {
+                    prefix.push(c);
+                } else if is_suffix_char(c) {
+                    suffix.push(c);
+                } else {
+                    token.push(c);
+                }
+                continue;
             } else if is_prompt_item_char(c) {
                 token.push(c);
                 continue;
@@ -71,7 +118,7 @@ pub fn render_prompt(sh: &shell::Shell, ps: &str) -> String {
         }
 
         if !token.is_empty() {
-            apply_token(sh, &mut prompt, &token);
+            apply_prompt_item(sh, &mut prompt, &token);
             token.clear();
         }
         prompt.push(c);