Integrate shfmt (#128)

* add shfmt compatibility

* add formatter tests

* add BashFormatter::as_cmd method

* Update src/modules/formatter.rs

Co-authored-by: Phoenix Himself <pkaras.it@gmail.com>

* refactor formatter.rs a little bit

* fix(rust): some changes

* fix(rust): some changes

* feat(readme): added line

* fix(merge): previous

* Update src/compiler.rs

Co-authored-by: Hubert Jabłoński <hubik080@gmail.com>

* Update src/modules/formatter.rs

Co-authored-by: Hubert Jabłoński <hubik080@gmail.com>

* Update src/modules/formatter.rs

Co-authored-by: Hubert Jabłoński <hubik080@gmail.com>

---------

Co-authored-by: Phoenix Himself <pkaras.it@gmail.com>
Co-authored-by: Daniele Scasciafratte <mte90net@gmail.com>
Co-authored-by: Hubert Jabłoński <hubik080@gmail.com>

README.md

@@ -4,7 +4,8 @@
 
 # Amber
 
-Programming language that compiles to Bash. It's a high level programming language that makes it easy to create shell scripts. It's particularly well suited for cloud services.
+Programming language that compiles to Bash. It's a high level programming language that makes it easy to create shell scripts. It's particularly well suited for cloud services.  
+If [shfmt](https://github.com/mvdan/sh) it is present in the machine it will be used after the compilation to prettify the Bash code generated.
 
 > [!Warning]
 > This software is not ready for extended usage.

src/compiler.rs

@@ -3,7 +3,8 @@ use chrono::prelude::*;
 use crate::docs::module::DocumentationModule;
 use itertools::Itertools;
 use crate::modules::block::Block;
-use crate::rules;
+use crate::modules::formatter::BashFormatter;
+use crate::{rules, Cli};
 use crate::translate::check_all_blocks;
 use crate::translate::module::TranslateModule;
 use crate::utils::{ParserMetadata, TranslateMetadata};
@@ -24,13 +25,15 @@ const AMBER_DEBUG_TIME: &str = "AMBER_DEBUG_TIME";
 pub struct AmberCompiler {
     pub cc: Compiler,
     pub path: Option<String>,
+    pub cli_opts: Cli
 }
 
 impl AmberCompiler {
-    pub fn new(code: String, path: Option<String>) -> AmberCompiler {
+    pub fn new(code: String, path: Option<String>, cli_opts: Cli) -> AmberCompiler {
         AmberCompiler {
             cc: Compiler::new("Amber", rules::get_rules()),
             path,
+            cli_opts
         }
         .load_code(AmberCompiler::strip_off_shebang(code))
     }
@@ -150,7 +153,15 @@ impl AmberCompiler {
                 time.elapsed().as_millis()
             );
         }
-        let res = result.join("\n");
+
+        let mut res = result.join("\n");
+
+        if !self.cli_opts.disable_format {
+            if let Some(formatter) = BashFormatter::get_available() {
+                res = formatter.format(res);
+            }
+        }
+
         let header = [
             include_str!("header.sh"),
             &("# version: ".to_owned() + option_env!("CARGO_PKG_VERSION").unwrap().to_string().as_str()),

src/main.rs

@@ -19,9 +19,9 @@ use std::io::prelude::*;
 use std::path::PathBuf;
 use std::process::Command;
 
-#[derive(Parser)]
+#[derive(Parser, Clone, Debug)]
 #[command(version, arg_required_else_help(true))]
-struct Cli {
+pub struct Cli {
     input: Option<PathBuf>,
     output: Option<PathBuf>,
 
@@ -31,27 +31,57 @@ struct Cli {
 
     /// Generate docs
     #[arg(long)]
-    docs: bool
+    docs: bool,
+
+    /// Don't format the output file
+    #[arg(long)]
+    disable_format: bool
+}
+
+impl Default for Cli {
+    fn default() -> Self {
+        Self {
+            input: None,
+            output: None,
+            eval: None,
+            docs: false,
+            disable_format: false
+        }
+    }
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
     let cli = Cli::parse();
     if cli.docs {
         handle_docs(cli)?;
-    } else if let Some(code) = cli.eval {
-        handle_eval(code)?;
+    } else if let Some(ref code) = cli.eval {
+        handle_eval(code.to_string(), cli)?;
     } else {
         handle_compile(cli)?;
     }
     Ok(())
 }
 
-fn handle_compile(cli: Cli) -> Result<(), Box<dyn Error>> {
-    if let Some(input) = cli.input {
+fn handle_compile(cli: Cli) -> Result<(), Box<dyn Error>> { 
+  if let Some(code) = cli.eval.clone() {
+        let code = format!("import * from \"std\"\n{code}");
+        match AmberCompiler::new(code, None, cli).compile() {
+            Ok((messages, code)) => {
+                messages.iter().for_each(|m| m.show());
+                (!messages.is_empty()).then(|| render_dash());
+                let exit_status = AmberCompiler::execute(code, &vec![])?;
+                std::process::exit(exit_status.code().unwrap_or(1));
+            }
+            Err(err) => {
+                err.show();
+                std::process::exit(1);
+            }
+        }
+    } else if let Some(input) = cli.input.clone() {
         let input = String::from(input.to_string_lossy());
         match fs::read_to_string(&input) {
             Ok(code) => {
-                match AmberCompiler::new(code, Some(input)).compile() {
+                match AmberCompiler::new(code, Some(input), cli.clone()).compile() {
                     Ok((messages, code)) => {
                         messages.iter().for_each(|m| m.show());
                         // Save to the output file
@@ -92,9 +122,9 @@ fn handle_compile(cli: Cli) -> Result<(), Box<dyn Error>> {
     Ok(())
 }
 
-fn handle_eval(code: String) -> Result<(), Box<dyn Error>> {
+fn handle_eval(code: String, cli: Cli) -> Result<(), Box<dyn Error>> {
     let code = format!("import * from \"std\"\n{code}");
-    match AmberCompiler::new(code, None).compile() {
+    match AmberCompiler::new(code, None, cli).compile() {
         Ok((messages, code)) => {
             messages.iter().for_each(|m| m.show());
             (!messages.is_empty()).then(|| render_dash());
@@ -109,15 +139,15 @@ fn handle_eval(code: String) -> Result<(), Box<dyn Error>> {
 }
 
 fn handle_docs(cli: Cli) -> Result<(), Box<dyn Error>> {
-    if let Some(input) = cli.input {
+    if let Some(ref input) = cli.input {
         let input = String::from(input.to_string_lossy());
         let output = {
-            let out = cli.output.unwrap_or_else(|| PathBuf::from("docs"));
+            let out = cli.output.clone().unwrap_or_else(|| PathBuf::from("docs"));
             String::from(out.to_string_lossy())
         };
         match fs::read_to_string(&input) {
             Ok(code) => {
-                match AmberCompiler::new(code, Some(input)).generate_docs(output) {
+                match AmberCompiler::new(code, Some(input), cli).generate_docs(output) {
                     Ok(_) => Ok(()),
                     Err(err) => {
                         err.show();

src/modules/formatter.rs

@@ -0,0 +1,75 @@
+use std::{io::{BufWriter, Write}, process::{Command, Stdio}};
+
+
+/// This mechanism is built to support multiple formatters.
+/// 
+/// The idea is that amber should find the one installed, verify that its compatible and use the best one possible.
+#[derive(Debug, Clone, Copy)]
+#[allow(non_camel_case_types)]
+pub enum BashFormatter {
+    /// https://github.com/mvdan/sh
+    shfmt
+}
+
+impl BashFormatter {
+    /// Get all available formatters, ordered: best ones at the start, worst at the end
+    pub fn get_all() -> Vec<BashFormatter> {
+        vec![
+            BashFormatter::shfmt
+        ]
+    }
+
+    /// Get available formatter
+    pub fn get_available() -> Option<BashFormatter> {
+        Self::get_all()
+          .iter()
+          .find(|fmt| fmt.is_available())
+          .map(|fmt| *fmt)
+    }
+
+    /// Check if current formatter is present in $PATH
+    pub fn is_available(self: &Self) -> bool {
+        match self {
+            BashFormatter::shfmt =>
+                Command::new("shfmt")
+                    .arg("--version")
+                    .stdout(Stdio::null())
+                    .stderr(Stdio::null())
+                    .spawn()
+                    .map(|mut x| x.wait())
+                    .is_ok()
+        }
+    }
+
+    #[allow(dead_code)] // used in tests
+    pub fn as_cmd<T: From<&'static str>>(self: &Self) -> T {
+        match self {
+            BashFormatter::shfmt => "shfmt".into()
+        }
+    }
+
+    /// Format code using the formatter
+    pub fn format(self: &Self, code: String) -> String {
+        match self {
+            BashFormatter::shfmt => {
+                let mut command = Command::new("shfmt")
+                    .stdout(Stdio::piped())
+                    .stdin(Stdio::piped())
+                    .arg("-i").arg("4") // indentation
+                    .arg("-ln").arg("bash") // language
+                    .spawn().expect("Couldn't spawn shfmt");
+
+                {
+                    let cmd_stdin = command.stdin.as_mut().expect("Couldn't get shfmt's stdin");
+                    let mut writer = BufWriter::new(cmd_stdin);
+                    writer.write_all(code.as_bytes()).expect("Couldn't write code to shfmt");
+                    writer.flush().expect("Couldn't flush shfmt's stdin");
+                }
+
+                let res = command.wait_with_output().expect("Couldn't wait for shfmt");
+
+                String::from_utf8(res.stdout).expect("shfmt returned non utf-8 output")
+            }
+        }
+    }
+}

src/modules/imports/import.rs

@@ -9,6 +9,7 @@ use crate::stdlib;
 use crate::utils::context::{Context, FunctionDecl};
 use crate::utils::{ParserMetadata, TranslateMetadata};
 use crate::translate::module::TranslateModule;
+use crate::Cli;
 use super::import_string::ImportString;
 
 #[derive(Debug, Clone)]
@@ -97,7 +98,7 @@ impl Import {
     }
 
     fn handle_compile_code(&mut self, meta: &mut ParserMetadata, imported_code: String) -> SyntaxResult {
-        match AmberCompiler::new(imported_code.clone(), Some(self.path.value.clone())).tokenize() {
+        match AmberCompiler::new(imported_code.clone(), Some(self.path.value.clone()), Cli::default()).tokenize() {
             Ok(tokens) => {
                 let mut block = Block::new();
                 // Save snapshot of current file

src/modules/mod.rs

@@ -11,6 +11,7 @@ pub mod types;
 pub mod imports;
 pub mod main;
 pub mod builtin;
+pub mod formatter;
 
 #[macro_export]
 macro_rules! handle_types {

src/tests/formatter.rs

@@ -0,0 +1,33 @@
+use std::{env, fs::{self, Permissions}, os::unix::fs::PermissionsExt};
+
+use crate::modules::formatter::BashFormatter;
+
+fn create_fake_binary(fmt: BashFormatter) {
+    let body = if cfg!(unix) {
+        "#!/usr/bin/env bash\nexit 0"
+    } else {
+        panic!("this test is not available for non-unix platforms")
+    };
+
+    let name: String = fmt.as_cmd();
+
+    fs::write(&name, body).expect("Couldn't write fake script");
+    fs::set_permissions(&name, Permissions::from_mode(0o755)).expect("Couldn't set perms for fake script");
+}
+
+#[test]
+fn all_exist() {
+    let path = env::var("PATH").expect("Cannot get $PATH");
+
+    env::set_var("PATH", format!("{path}:./")); // temporary unset to ensure that shfmt exists in $PATH
+    let fmts = BashFormatter::get_all();
+    for fmt in fmts {
+        create_fake_binary(fmt);
+        assert_eq!(fmt.is_available(), true);
+        assert_eq!(BashFormatter::get_available().is_some(), true);
+        fs::remove_file(fmt.as_cmd::<String>()).expect("Couldn't remove formatter's fake binary");
+    }
+
+    env::set_var("PATH", &path);
+    assert_eq!(env::var("PATH").expect("Cannot get $PATH"), path);
+}

src/tests/mod.rs

@@ -1,19 +1,21 @@
 use crate::compiler::AmberCompiler;
+use crate::Cli;
 
 pub mod cli;
+pub mod formatter;
 pub mod stdlib;
 pub mod validity;
 
 #[macro_export]
 macro_rules! test_amber {
     ($code:expr, $result:expr) => {{
-        match AmberCompiler::new($code.to_string(), None).test_eval() {
+        match AmberCompiler::new($code.to_string(), None, Cli::default()).test_eval() {
             Ok(result) => assert_eq!(result.trim_end_matches('\n'), $result),
             Err(err) => panic!("ERROR: {}", err.message.unwrap()),
         }
     }};
 }
 
 pub fn compile_code<T: Into<String>>(code: T) -> String {
-    AmberCompiler::new(code.into(), None).compile().unwrap().1
+    AmberCompiler::new(code.into(), None, Cli::default()).compile().unwrap().1
 }

src/tests/stdlib.rs

@@ -4,6 +4,7 @@ use test_generator::test_resources;
 use crate::compiler::AmberCompiler;
 use crate::test_amber;
 use crate::tests::compile_code;
+use crate::Cli;
 use std::path::Path;
 use std::fs;
 use std::time::Duration;

src/tests/validity.rs

@@ -3,6 +3,7 @@ extern crate test_generator;
 use test_generator::test_resources;
 use crate::compiler::AmberCompiler;
 use crate::test_amber;
+use crate::Cli;
 use std::fs;
 use std::path::Path;