Add nix support (#54)

* Add nix support

Co-authored-by: John-John Tedro <udoprog@tedro.se>

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        rust: ["1.58", stable, nightly]
+        rust: ['1.66', stable, nightly]
     steps:
     - uses: actions/checkout@v3
     - uses: dtolnay/rust-toolchain@master

.github/workflows/weekly.yml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        rust: ["1.58", stable]
+        rust: ['1.66', stable]
     steps:
     - uses: actions/checkout@v3
     - uses: dtolnay/rust-toolchain@master

Cargo.toml

@@ -3,7 +3,7 @@ name = "genco"
 version = "0.17.8"
 authors = ["John-John Tedro <udoprog@tedro.se>"]
 edition = "2018"
-rust-version = "1.58"
+rust-version = "1.66"
 description = "A whitespace-aware quasiquoter for beautiful code generation."
 documentation = "https://docs.rs/genco"
 readme = "README.md"

examples/nix.rs

@@ -0,0 +1,34 @@
+use genco::fmt;
+use genco::prelude::*;
+
+fn main() -> anyhow::Result<()> {
+    let nixpkgs = &nix::inherit("inputs", "nixpkgs");
+    let pkgs = &nix::variable(
+        "pkgs",
+        quote! {
+            import $nixpkgs {
+                inherit ($nixpkgs) system;
+                config.allowUnfree = true;
+                overlays = [];
+            }
+        },
+    );
+    let mk_default = &nix::with("lib", "mkDefault");
+
+    let tokens = quote! {
+        {
+            imports = [];
+            environment.systemPackages = with $pkgs; [];
+            networking.useDHCP = $mk_default true;
+        }
+    };
+
+    let stdout = std::io::stdout();
+    let mut w = fmt::IoWriter::new(stdout.lock());
+
+    let fmt = fmt::Config::from_lang::<Nix>();
+    let config = nix::Config::default();
+
+    tokens.format_file(&mut w.as_formatter(&fmt), &config)?;
+    Ok(())
+}

genco-macros/Cargo.toml

@@ -3,7 +3,7 @@ name = "genco-macros"
 version = "0.17.8"
 authors = ["John-John Tedro <udoprog@tedro.se>"]
 edition = "2018"
-rust-version = "1.58"
+rust-version = "1.66"
 description = """
 A whitespace-aware quasiquoter for beautiful code generation.
 """

src/fmt/cursor.rs

@@ -90,7 +90,7 @@ where
     where
         P: Parse<L>,
     {
-        if let Some(item) = self.items.get(0) {
+        if let Some(item) = self.items.first() {
             P::peek(item)
         } else {
             false

src/fmt/formatter.rs

@@ -13,14 +13,14 @@ static TABS: &str =
     "\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t";
 
 #[derive(Debug, Clone, Copy)]
-enum Line {
+enum Whitespace {
     Initial,
     None,
     Push,
     Line,
 }
 
-impl Line {
+impl Whitespace {
     /// Convert into an indentation level.
     ///
     /// If we return `None`, no indentation nor lines should be written since we
@@ -35,7 +35,7 @@ impl Line {
     }
 }
 
-impl Default for Line {
+impl Default for Whitespace {
     fn default() -> Self {
         Self::None
     }
@@ -50,7 +50,7 @@ pub struct Formatter<'a> {
     /// How many lines we want to add to the output stream.
     ///
     /// This will only be realized if we push non-whitespace.
-    line: Line,
+    line: Whitespace,
     /// How many spaces we want to add to the output stream.
     ///
     /// This will only be realized if we push non-whitespace, and will be reset
@@ -65,7 +65,7 @@ impl<'a> Formatter<'a> {
     pub(crate) fn new(write: &'a mut (dyn fmt::Write + 'a), config: &'a Config) -> Formatter<'a> {
         Formatter {
             write,
-            line: Line::Initial,
+            line: Whitespace::Initial,
             spaces: 0usize,
             indent: 0i16,
             config,
@@ -90,7 +90,7 @@ impl<'a> Formatter<'a> {
     ///
     /// This will also reset any whitespace we have pending.
     pub(crate) fn write_trailing_line(&mut self) -> fmt::Result {
-        self.line = Line::default();
+        self.line = Whitespace::default();
         self.spaces = 0;
         self.write.write_trailing_line(self.config)?;
         Ok(())
@@ -108,9 +108,9 @@ impl<'a> Formatter<'a> {
 
     fn push(&mut self) {
         self.line = match self.line {
-            Line::Initial => return,
-            Line::Line => return,
-            _ => Line::Push,
+            Whitespace::Initial => return,
+            Whitespace::Line => return,
+            _ => Whitespace::Push,
         };
 
         self.spaces = 0;
@@ -119,8 +119,8 @@ impl<'a> Formatter<'a> {
     /// Push a new line.
     fn line(&mut self) {
         self.line = match self.line {
-            Line::Initial => return,
-            _ => Line::Line,
+            Whitespace::Initial => return,
+            _ => Whitespace::Line,
         };
 
         self.spaces = 0;

src/lang/mod.rs

@@ -23,6 +23,7 @@ pub mod dart;
 pub mod go;
 pub mod java;
 pub mod js;
+pub mod nix;
 pub mod python;
 pub mod rust;
 pub mod swift;
@@ -33,6 +34,7 @@ pub use self::dart::Dart;
 pub use self::go::Go;
 pub use self::java::Java;
 pub use self::js::JavaScript;
+pub use self::nix::Nix;
 pub use self::python::Python;
 pub use self::rust::Rust;
 pub use self::swift::Swift;