Rollup merge of #51791 - GuillaumeGomez:minify-css, r=estebank

Minify css

Sizes changes:

```
dark.css: 8821 => 7804 (~11%)
light.css: 8587 => 7565 (~11%)
rustdoc.css: 22364 => 17818 (~20%)
settings.css: 1384 => 1236 (~10%)
```

So obviously, the bigger the file, the bigger minification.

r? @QuietMisdreavus

Author: pietroalbini

src/Cargo.lock

@@ -1220,7 +1220,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "minifier"
-version = "0.0.11"
+version = "0.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "regex 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2426,7 +2426,7 @@ dependencies = [
 name = "rustdoc"
 version = "0.0.0"
 dependencies = [
- "minifier 0.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "minifier 0.0.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "pulldown-cmark 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -3263,7 +3263,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum mdbook 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "90b5a8d7e341ceee5db3882a06078d42661ddcfa2b3687319cc5da76ec4e782f"
 "checksum memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "796fba70e76612589ed2ce7f45282f5af869e0fdd7cc6199fa1aa1f1d591ba9d"
 "checksum memoffset 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0f9dc261e2b62d7a622bf416ea3c5245cdd5d9a7fcc428c0d06804dfce1775b3"
-"checksum minifier 0.0.11 (registry+https://github.com/rust-lang/crates.io-index)" = "26f3e36a4db1981b16567e4abfd6ddc3641bc9b950bdc868701f656bf9b74bdd"
+"checksum minifier 0.0.14 (registry+https://github.com/rust-lang/crates.io-index)" = "78cb57f9a385530d60f2d67f6e108050b478b7a0ffd0bb9c350803e1356535dd"
 "checksum miniz-sys 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "609ce024854aeb19a0ef7567d348aaa5a746b32fb72e336df7fcc16869d7e2b4"
 "checksum miow 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9224c91f82b3c47cf53dcf78dfaa20d6888fbcc5d272d5f2fcdf8a697f3c987d"
 "checksum nibble_vec 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "c8d77f3db4bce033f4d04db08079b2ef1c3d02b44e86f25d08886fafa7756ffa"

src/librustdoc/Cargo.toml

@@ -9,5 +9,5 @@ path = "lib.rs"
 
 [dependencies]
 pulldown-cmark = { version = "0.1.2", default-features = false }
-minifier = "0.0.11"
+minifier = "0.0.14"
 tempfile = "3"

src/librustdoc/html/render.rs

@@ -42,6 +42,7 @@ use std::collections::{BTreeMap, HashSet, VecDeque};
 use std::default::Default;
 use std::error;
 use std::fmt::{self, Display, Formatter, Write as FmtWrite};
+use std::ffi::OsStr;
 use std::fs::{self, File, OpenOptions};
 use std::io::prelude::*;
 use std::io::{self, BufWriter, BufReader};
@@ -756,10 +757,12 @@ fn write_shared(cx: &Context,
     // Add all the static files. These may already exist, but we just
     // overwrite them anyway to make sure that they're fresh and up-to-date.
 
-    write(cx.dst.join(&format!("rustdoc{}.css", cx.shared.resource_suffix)),
-          include_bytes!("static/rustdoc.css"))?;
-    write(cx.dst.join(&format!("settings{}.css", cx.shared.resource_suffix)),
-          include_bytes!("static/settings.css"))?;
+    write_minify(cx.dst.join(&format!("rustdoc{}.css", cx.shared.resource_suffix)),
+                 include_str!("static/rustdoc.css"),
+                 enable_minification)?;
+    write_minify(cx.dst.join(&format!("settings{}.css", cx.shared.resource_suffix)),
+                 include_str!("static/settings.css"),
+                 enable_minification)?;
 
     // To avoid "light.css" to be overwritten, we'll first run over the received themes and only
     // then we'll run over the "official" styles.
@@ -781,11 +784,13 @@ fn write_shared(cx: &Context,
           include_bytes!("static/brush.svg"))?;
     write(cx.dst.join(&format!("wheel{}.svg", cx.shared.resource_suffix)),
           include_bytes!("static/wheel.svg"))?;
-    write(cx.dst.join(&format!("light{}.css", cx.shared.resource_suffix)),
-          include_bytes!("static/themes/light.css"))?;
+    write_minify(cx.dst.join(&format!("light{}.css", cx.shared.resource_suffix)),
+                 include_str!("static/themes/light.css"),
+                 enable_minification)?;
     themes.insert("light".to_owned());
-    write(cx.dst.join(&format!("dark{}.css", cx.shared.resource_suffix)),
-          include_bytes!("static/themes/dark.css"))?;
+    write_minify(cx.dst.join(&format!("dark{}.css", cx.shared.resource_suffix)),
+                 include_str!("static/themes/dark.css"),
+                 enable_minification)?;
     themes.insert("dark".to_owned());
 
     let mut themes: Vec<&String> = themes.iter().collect();
@@ -857,10 +862,19 @@ themePicker.onblur = handleThemeButtonsBlur;
 
     if let Some(ref css) = cx.shared.css_file_extension {
         let out = cx.dst.join(&format!("theme{}.css", cx.shared.resource_suffix));
-        try_err!(fs::copy(css, out), css);
+        if !enable_minification {
+            try_err!(fs::copy(css, out), css);
+        } else {
+            let mut f = try_err!(File::open(css), css);
+            let mut buffer = String::with_capacity(1000);
+
+            try_err!(f.read_to_string(&mut buffer), css);
+            write_minify(out, &buffer, enable_minification)?;
+        }
     }
-    write(cx.dst.join(&format!("normalize{}.css", cx.shared.resource_suffix)),
-          include_bytes!("static/normalize.css"))?;
+    write_minify(cx.dst.join(&format!("normalize{}.css", cx.shared.resource_suffix)),
+                 include_str!("static/normalize.css"),
+                 enable_minification)?;
     write(cx.dst.join("FiraSans-Regular.woff"),
           include_bytes!("static/FiraSans-Regular.woff"))?;
     write(cx.dst.join("FiraSans-Medium.woff"),
@@ -1051,7 +1065,12 @@ fn write(dst: PathBuf, contents: &[u8]) -> Result<(), Error> {
 
 fn write_minify(dst: PathBuf, contents: &str, enable_minification: bool) -> Result<(), Error> {
     if enable_minification {
-        write(dst, minifier::js::minify(contents).as_bytes())
+        if dst.extension() == Some(&OsStr::new("css")) {
+            let res = try_none!(minifier::css::minify(contents).ok(), &dst);
+            write(dst, res.as_bytes())
+        } else {
+            write(dst, minifier::js::minify(contents).as_bytes())
+        }
     } else {
         write(dst, contents.as_bytes())
     }