1 files changed, 161 insertions, 0 deletions
diff --git a/mling/src/cargo_style.rs b/mling/src/cargo_style.rs
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+++ b/mling/src/cargo_style.rs
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+use colored::Colorize;
+
+/// Formats a message in cargo-style format with a bold green prefix.
+///
+/// The message should be in the format `prefix: content`. The prefix will be
+/// bold green and right-padded to 12 characters. If there is no colon in the
+/// string, the entire string is printed as content with an empty prefix.
+///
+/// # Macros
+///
+/// - `format_cargo!("prefix: {}", arg)` — format-style invocation
+/// - `format_cargo!(expr)` — direct expression invocation
+///
+/// # Panics
+///
+/// Panics if the prefix (text before the first `:`) exceeds 12 characters.
+///
+/// # Examples
+///
+/// ```
+/// format_cargo!("Compiling: hello.rs");
+/// // Output: "   Compiling hello.rs" (green bold "Compiling" padded to 12)
+/// ```
+#[macro_export]
+macro_rules! format_cargo {
+    ($fmt:literal, $($arg:tt)*) => {
+        $crate::format_cargo(format!($fmt, $($arg)*))
+    };
+    ($cmd:expr) => {
+        $crate::format_cargo($cmd)
+    };
+}
+
+/// Formats an error message in cargo-style format with a bold red "error" prefix.
+///
+/// # Macros
+///
+/// - `eformat_cargo!("prefix: {}", arg)` — format-style invocation
+/// - `eformat_cargo!(expr)` — direct expression invocation
+///
+/// # Examples
+///
+/// ```
+/// eformat_cargo!("failed to parse input");
+/// // Output: "error: failed to parse input" (red bold "error")
+/// ```
+#[macro_export]
+macro_rules! eformat_cargo {
+    ($fmt:literal, $($arg:tt)*) => {
+        $crate::eformat_cargo(format!($fmt, $($arg)*))
+    };
+    ($cmd:expr) => {
+        $crate::eformat_cargo($cmd)
+    };
+}
+
+/// Print a message in cargo-style format with a bold green prefix.
+///
+/// # Macros
+///
+/// - `println_cargo!("prefix: {}", arg)` — format-style invocation
+/// - `println_cargo!(expr)` — direct expression invocation
+///
+/// # Examples
+///
+/// ```
+/// println_cargo!("Compiling: hello.rs");
+/// ```
+#[macro_export]
+macro_rules! println_cargo {
+    ($fmt:literal, $($arg:tt)*) => {
+        println!("{}", $crate::format_cargo(format!($fmt, $($arg)*)))
+    };
+    ($cmd:expr) => {
+        println!("{}", $crate::format_cargo($cmd))
+    };
+}
+
+/// Print an error message in cargo-style format with a bold red "error" prefix.
+///
+/// # Macros
+///
+/// - `eprintln_cargo!("prefix: {}", arg)` — format-style invocation
+/// - `eprintln_cargo!(expr)` — direct expression invocation
+///
+/// # Examples
+///
+/// ```
+/// eprintln_cargo!("failed to parse input");
+/// ```
+#[macro_export]
+macro_rules! eprintln_cargo {
+    ($fmt:literal, $($arg:tt)*) => {
+        eprintln!("{}", $crate::eformat_cargo(format!($fmt, $($arg)*)))
+    };
+    ($cmd:expr) => {
+        eprintln!("{}", $crate::eformat_cargo($cmd))
+    };
+}
+
+/// Format a message in cargo style format, with bold green prefix.
+///
+/// The input string is split at the first `:`. The part before the colon becomes
+/// the prefix (bold green, right-padded to 12 characters), and the part after
+/// becomes the content.
+///
+/// If no colon is found, the entire string is treated as content and no prefix
+/// is shown.
+///
+/// # Panics
+///
+/// Panics if the prefix (text before the first `:`) exceeds 12 characters.
+///
+/// # Examples
+///
+/// ```ignore
+/// format_cargo("Compiling: my_program.rs");
+/// // returns "   Compiling my_program.rs"
+/// ```
+pub fn format_cargo(str: impl Into<String>) -> String {
+    let s = str.into();
+    let (prefix, content) = if let Some(pos) = s.find(':') {
+        (
+            s[..pos].trim().to_string(),
+            s[pos + 1..].trim_start().to_string(),
+        )
+    } else {
+        (String::new(), s.trim().to_string())
+    };
+
+    assert!(
+        prefix.len() <= 12,
+        "prefix length exceeds 12: '{}' has length {}",
+        prefix,
+        prefix.len()
+    );
+
+    let padding = " ".repeat(12 - prefix.len());
+
+    format!(
+        "{}{} {}",
+        padding,
+        prefix.bold().bright_green(),
+        content.trim()
+    )
+}
+
+/// Format an error message in cargo style format, with bold red "error" prefix.
+///
+/// The input string is printed as the error content, prefixed by a bold red
+/// `error:` label.
+///
+/// # Examples
+///
+/// ```ignore
+/// eformat_cargo("something went wrong");
+/// // returns "error: something went wrong"
+/// ```
+pub fn eformat_cargo(str: impl Into<String>) -> String {
+    format!("{}: {}", "error".bold().bright_red(), str.into())
+}