regex: Remove in-tree version

The regex library was largely used for non-critical aspects of the compiler and
various external tooling. The library at this point is duplicated with its
out-of-tree counterpart and as such imposes a bit of a maintenance overhead as
well as compile time hit for the compiler itself.

The last major user of the regex library is the libtest library, using regexes
for filters when running tests. This removal means that the filtering has gone
back to substring matching rather than using regexes.

3 files changed, 45 insertions, 49 deletions

diff --git a/src/rustbook/book.rs b/src/rustbook/book.rs
index 20346449fd1..3047e93137f 100644
--- a/src/rustbook/book.rs
+++ b/src/rustbook/book.rs
@@ -13,7 +13,6 @@
 use std::io::BufferedReader;
 use std::iter;
 use std::iter::AdditiveIterator;
-use regex::Regex;
 
 pub struct BookItem {
     pub title: String,
@@ -94,8 +93,6 @@ pub fn parse_summary<R: Reader>(input: R, src: &Path) -> Result<Book, Vec<String
         }
     }
 
-    let regex = r"(?P<indent>[\t ]*)\*[:space:]*\[(?P<title>.*)\]\((?P<path>.*)\)";
-    let item_re = Regex::new(regex).unwrap();
     let mut top_items = vec!();
     let mut stack = vec!();
     let mut errors = vec!();
@@ -117,45 +114,51 @@ pub fn parse_summary<R: Reader>(input: R, src: &Path) -> Result<Book, Vec<String
             }
         };
 
-        item_re.captures(&line[]).map(|cap| {
-            let given_path = cap.name("path");
-            let title = cap.name("title").unwrap().to_string();
-
-            let path_from_root = match src.join(given_path.unwrap()).path_relative_from(src) {
-                Some(p) => p,
-                None => {
-                    errors.push(format!("paths in SUMMARY.md must be relative, \
-                                         but path '{}' for section '{}' is not.",
-                                         given_path.unwrap(), title));
-                    Path::new("")
-                }
-            };
-            let path_to_root = Path::new(iter::repeat("../")
-                                             .take(path_from_root.components().count() - 1)
-                                             .collect::<String>());
-            let item = BookItem {
-                title: title,
-                path: path_from_root,
-                path_to_root: path_to_root,
-                children: vec!(),
-            };
-            let level = cap.name("indent").unwrap().chars().map(|c| {
-                match c {
-                    ' ' => 1us,
-                    '\t' => 4,
-                    _ => unreachable!()
-                }
-            }).sum() / 4 + 1;
-
-            if level > stack.len() + 1 {
-                errors.push(format!("section '{}' is indented too deeply; \
-                                     found {}, expected {} or less",
-                                    item.title, level, stack.len() + 1));
-            } else if level <= stack.len() {
-                collapse(&mut stack, &mut top_items, level);
+        let star_idx = match line.find_str("*") { Some(i) => i, None => continue };
+
+        let start_bracket = star_idx + line[star_idx..].find_str("[").unwrap();
+        let end_bracket = start_bracket + line[start_bracket..].find_str("](").unwrap();
+        let start_paren = end_bracket + 1;
+        let end_paren = start_paren + line[start_paren..].find_str(")").unwrap();
+
+        let given_path = &line[start_paren + 1 .. end_paren];
+        let title = line[start_bracket + 1..end_bracket].to_string();
+        let indent = &line[..star_idx];
+
+        let path_from_root = match src.join(given_path).path_relative_from(src) {
+            Some(p) => p,
+            None => {
+                errors.push(format!("paths in SUMMARY.md must be relative, \
+                                     but path '{}' for section '{}' is not.",
+                                     given_path, title));
+                Path::new("")
             }
-            stack.push(item)
-        });
+        };
+        let path_to_root = Path::new(iter::repeat("../")
+                                         .take(path_from_root.components().count() - 1)
+                                         .collect::<String>());
+        let item = BookItem {
+            title: title,
+            path: path_from_root,
+            path_to_root: path_to_root,
+            children: vec!(),
+        };
+        let level = indent.chars().map(|c| {
+            match c {
+                ' ' => 1us,
+                '\t' => 4,
+                _ => unreachable!()
+            }
+        }).sum() / 4 + 1;
+
+        if level > stack.len() + 1 {
+            errors.push(format!("section '{}' is indented too deeply; \
+                                 found {}, expected {} or less",
+                                item.title, level, stack.len() + 1));
+        } else if level <= stack.len() {
+            collapse(&mut stack, &mut top_items, level);
+        }
+        stack.push(item)
     }
 
     if errors.is_empty() {
diff --git a/src/rustbook/build.rs b/src/rustbook/build.rs
index 50a6ad43aee..93601c0f61b 100644
--- a/src/rustbook/build.rs
+++ b/src/rustbook/build.rs
@@ -22,8 +22,6 @@ use book::{Book, BookItem};
 use css;
 use javascript;
 
-use regex::Regex;
-
 use rustdoc;
 
 struct Build;
@@ -81,9 +79,6 @@ fn render(book: &Book, tgt: &Path) -> CliResult<()> {
 
         let out_path = tgt.join(item.path.dirname());
 
-        let regex = r"\[(?P<title>[^]]*)\]\((?P<url_stem>[^)]*)\.(?P<ext>md|markdown)\)";
-        let md_urls = Regex::new(regex).unwrap();
-
         let src;
         if os::args().len() < 3 {
             src = os::getcwd().unwrap().clone();
@@ -94,7 +89,7 @@ fn render(book: &Book, tgt: &Path) -> CliResult<()> {
         let markdown_data = try!(File::open(&src.join(&item.path)).read_to_string());
         let preprocessed_path = tmp.path().join(item.path.filename().unwrap());
         {
-            let urls = md_urls.replace_all(&markdown_data[], "[$title]($url_stem.html)");
+            let urls = markdown_data.replace(".md)", ".html)");
             try!(File::create(&preprocessed_path)
                       .write_str(&urls[]));
         }
diff --git a/src/rustbook/main.rs b/src/rustbook/main.rs
index ea72c653087..cbd29004097 100644
--- a/src/rustbook/main.rs
+++ b/src/rustbook/main.rs
@@ -11,8 +11,6 @@
 #![feature(slicing_syntax, box_syntax)]
 #![allow(unstable)]
 
-extern crate regex;
-
 extern crate rustdoc;
 
 use std::os;