Build scripts, stable

* Fix tests failing to compile properly (used take_while instead of filter :p)

* Added support for build scripts, which will prompt the user for permission before running. This is a simple `build.c` file at the top level of your project. Currently the only "command" it has is to set the `src` directory, for the case of preprocessing.

* Removed redundant use of const blocks, since const assignments already allowed constant blocks expressions. Also removed the blocks entirely and just opted for more generic errors.

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "cpkg"
 description = "A dead simple C package manager."
-version = "0.11.0"
+version = "0.12.0"
 edition = "2021"
 
 authors = ["David Cruz <[email protected]>"]

src/components/compiler.rs

@@ -104,20 +104,5 @@ pub fn try_locate(proj: Option<&crate::Project>) -> anyhow::Result<Box<dyn Compi
 		}
 	}
 
-	/* todo: cleaner impl when const for / const iterators exist */
-	const SUPPORTED_NAMES: &[&str] = &const {
-		let mut i = 0;
-		let mut arr = [""; SUPPORTED.len()];
-		while i < SUPPORTED.len() {
-			arr[i] = SUPPORTED[i].0;
-			i += 1;
-		}
-
-		arr
-	};
-
-	Err(anyhow::anyhow!(
-		"Couldn't find {}",
-		SUPPORTED_NAMES.join(" or ")
-	))
+	Err(anyhow::anyhow!("Couldn't find a compiler backend."))
 }

src/components/docgen.rs

@@ -122,20 +122,5 @@ pub fn try_locate(proj: &crate::Project) -> anyhow::Result<Box<dyn Docgen>> {
 		}
 	}
 
-	/* todo: cleaner impl when const for / const iterators exist */
-	const SUPPORTED_NAMES: &[&str] = &const {
-		let mut i = 0;
-		let mut arr = [""; SUPPORTED.len()];
-		while i < SUPPORTED.len() {
-			arr[i] = SUPPORTED[i].0;
-			i += 1;
-		}
-
-		arr
-	};
-
-	Err(anyhow::anyhow!(
-		"Couldn't find {}",
-		SUPPORTED_NAMES.join(" or ")
-	))
+	Err(anyhow::anyhow!("Couldn't find a docgen backend"))
 }

src/components/format.rs

@@ -63,18 +63,6 @@ const SUPPORTED: &[(&'static str, fn() -> Box<dyn Format>)] = &[
 	( "uncrustify", || Box::new(Uncrustify) )
 ];
 
-/* todo: cleaner impl when const for / const iterators exist */
-const SUPPORTED_NAMES: &[&str] = &const {
-	let mut i = 0;
-	let mut arr = [""; SUPPORTED.len()];
-	while i < SUPPORTED.len() {
-		arr[i] = SUPPORTED[i].0;
-		i += 1;
-	}
-
-	arr
-};
-
 /// Tries to find an available C formatter
 /// Currently only supports clang-format.
 pub fn try_locate(proj: &crate::Project) -> anyhow::Result<Box<dyn Format>> {
@@ -106,8 +94,5 @@ pub fn try_locate(proj: &crate::Project) -> anyhow::Result<Box<dyn Format>> {
 		}
 	}
 
-	Err(anyhow::anyhow!(
-		"Couldn't find {}",
-		SUPPORTED_NAMES.join(" or ")
-	))
+	Err(anyhow::anyhow!("Couldn't find a formatting backend"))
 }

src/main.rs

@@ -11,6 +11,15 @@ use project::*;
 mod config;
 use config::*;
 
+fn build_script_check() -> bool {
+	println!("This project needs a build script to run. Accept? (y/n)");
+
+	let mut s = String::new();
+	std::io::stdin().read_line(&mut s).unwrap();
+
+	s.find("y").is_some()
+}
+
 fn main() -> anyhow::Result<()> {
 	let args: cli::Cli = clap::Parser::parse();
 	let cd = std::env::current_dir()?;
@@ -60,7 +69,11 @@ fn main() -> anyhow::Result<()> {
 
 			let now = std::time::Instant::now();
 
-			proj.build(compiler::try_locate(Some(&proj))?.as_ref(), bin)?;
+			proj.build(
+				compiler::try_locate(Some(&proj))?.as_ref(),
+				bin,
+				build_script_check,
+			)?;
 
 			println!(
 				"Successfully built program(s) in {}s",
@@ -112,7 +125,11 @@ fn main() -> anyhow::Result<()> {
 			}
 
 			let proj = proj?;
-			let out = proj.build(compiler::try_locate(Some(&proj))?.as_ref(), bin)?;
+			let out = proj.build(
+				compiler::try_locate(Some(&proj))?.as_ref(),
+				bin,
+				build_script_check,
+			)?;
 
 			std::process::Command::new(out).spawn()?;
 		}
@@ -239,9 +256,7 @@ fn main() -> anyhow::Result<()> {
 				.tempfile()?
 				.into_temp_path();
 
-			let temp_bin = tempfile::Builder::new()
-				.tempfile()?
-				.into_temp_path();
+			let temp_bin = tempfile::Builder::new().tempfile()?.into_temp_path();
 
 			let mut stdout = std::io::stdout().lock();
 			let mut buffer = String::new();
@@ -265,7 +280,12 @@ fn main() -> anyhow::Result<()> {
 					"#)
 				)?;
 
-				match backend.compile(&[temp_repl.to_path_buf()], &[], &temp_bin, &["-w".to_owned(), "-fdiagnostics-color=always".to_owned()]) {
+				match backend.compile(
+					&[temp_repl.to_path_buf()],
+					&[],
+					&temp_bin,
+					&["-w".to_owned(), "-fdiagnostics-color=always".to_owned()],
+				) {
 					Ok(_) => {
 						let mut out = std::process::Command::new(&temp_bin).output()?;
 
@@ -289,7 +309,7 @@ fn main() -> anyhow::Result<()> {
 					}
 					Err(e) => {
 						print!("{e}");
-					},
+					}
 				}
 			}
 		}

src/project.rs

@@ -20,6 +20,9 @@ impl<'a> Project<'a> {
 	/// Folder containing test files
 	const TESTS: &'static str = "tests";
 
+	/// Prefix for build commands
+	const BUILD_COMMAND_PREFIX: &'static str = "cpkg::";
+
 	/*
 		Paths
 	*/
@@ -291,8 +294,8 @@ impl<'a> Project<'a> {
 		inline_tests.chain(explicit_tests)
 	}
 
-	pub fn c_files(&self) -> impl std::iter::Iterator<Item = std::path::PathBuf> {
-		walkdir::WalkDir::new(self.src())
+	pub fn c_files(&self, src: impl AsRef<std::path::Path>) -> impl std::iter::Iterator<Item = std::path::PathBuf> {
+		walkdir::WalkDir::new(src)
 			.into_iter()
 			.flat_map(std::convert::identity)
 			.filter(|e| e.path().is_file())
@@ -344,18 +347,57 @@ impl<'a> Project<'a> {
 		&self,
 		backend: &dyn crate::compiler::Compiler,
 		entrypoint: &Option<String>,
+		can_run_build: impl FnOnce() -> bool,
 	) -> anyhow::Result<std::path::PathBuf> {
-		let src = self.src();
+		let mut src = self.src();
 
 		if !self.target().exists() {
 			std::fs::create_dir(self.target())?;
 		}
 
+		let build_c = self.path.join("build.c");
+		if build_c.exists() {
+			if can_run_build() {
+				let t = tempfile::Builder::new().tempfile()?.into_temp_path();
+
+				backend.compile(&[build_c], &[], &t, &[])?;
+
+				let out = std::process::Command::new(&t).output()?;
+
+				if !out.status.success() {
+					anyhow::bail!(
+						"Build script failed: {}",
+						String::from_utf8_lossy(&out.stderr)
+					);
+				}
+
+				let out = String::from_utf8_lossy(&out.stdout);
+				let mut ptr = 0;
+
+				while let Some(r) = out[ptr..].find(Self::BUILD_COMMAND_PREFIX) {
+					let cmd = out[r..].split_once(" \t\n").map(|p| p.0).unwrap_or(&out[r..]);
+					let cmd = &cmd[Self::BUILD_COMMAND_PREFIX.len()..];
+
+					if cmd.starts_with("set_src") {
+						if let Some((_, to)) = cmd.split_once('=') {
+							src = std::env::current_dir()?.join(to.trim());
+						}
+					}
+
+					ptr = r + 1;
+				}
+			} else {
+				anyhow::bail!(
+					"This project requires a build script to run, but was not permitted to run it."
+				);
+			}
+		}
+
 		if let Some(entrypoint) = entrypoint {
 			let entrypoint = src.join(entrypoint).with_extension("c");
 			let out = self.build_out(Some(&entrypoint));
 
-			let mut c_files = self.c_files().collect::<Vec<_>>();
+			let mut c_files = self.c_files(&src).collect::<Vec<_>>();
 			if let Some(pos) = c_files.iter().position(|p| **p == entrypoint) {
 				/* Swap to beginning, so that its main is registered first by linker. */
 				c_files.swap(pos, 0);
@@ -366,7 +408,7 @@ impl<'a> Project<'a> {
 			let mut flags = self.build_flags(backend).to_vec();
 			flags.push("-zmuldefs".to_owned()); /* Tell linker to allow multiple entrypoints, taking first encountered */
 
-			backend.compile(&c_files, &[&self.vendor(), &src], &out, &flags)?;
+			backend.compile(&c_files, &[&src, &self.vendor()], &out, &flags)?;
 
 			Ok(out)
 		} else {
@@ -375,7 +417,7 @@ impl<'a> Project<'a> {
 			let out = self.build_out(None);
 
 			if main.exists() {
-				let c_files = self.c_files().collect::<Vec<_>>();
+				let c_files = self.c_files(&src).collect::<Vec<_>>();
 				let flags = self.build_flags(backend);
 
 				backend.compile(&c_files, &[&self.vendor(), &src], &out, &flags)?;
@@ -398,8 +440,8 @@ impl<'a> Project<'a> {
 		let src = self.src();
 
 		let mut c_files = self
-			.c_files()
-			.take_while(|f| f.file_name().unwrap() != "main.c")
+			.c_files(&src)
+			.filter(|f| f.file_name().unwrap() != "main.c")
 			.collect::<Vec<_>>();
 
 		let out_dir = Self::get_or_mkdir(Self::get_or_mkdir(self.target())?.join("test"))?;