Auto merge of #436 - rust-lang:ag/misc-fixes, r=BurntSushi

remove regex plugin + rollup + chores

This PR:

* Removes the regex compiler plugin. It's been broken for quite some time and nobody has seemed to notice. It's time for it to go. See commit cc7b00c for details.
* Setup a Cargo workspace for this repo.
* Update deps in various places. This includes updating simd to `0.2.1`, which fixes a build failure on Rust nightly.
* Name the frequency analysis based memchr search "freqy packed."
* Rolls up the other open PRs #401, #410 and #433.

.travis.yml

@@ -26,3 +26,6 @@ env:
 notifications:
   email:
     on_success: never
+branches:
+  only:
+    - master

Cargo.toml

@@ -5,7 +5,7 @@ authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 readme = "README.md"
 repository = "https://github.com/rust-lang/regex"
-documentation = "https://doc.rust-lang.org/regex"
+documentation = "https://docs.rs/regex"
 homepage = "https://github.com/rust-lang/regex"
 description = """
 An implementation of regular expressions for Rust. This implementation uses
@@ -17,6 +17,9 @@ categories = ["text-processing"]
 travis-ci = { repository = "rust-lang/regex" }
 appveyor = { repository = "rust-lang-libs/regex" }
 
+[workspace]
+members = ["bench", "regex-capi", "regex-debug", "regex-syntax"]
+
 [dependencies]
 # For very fast prefix literal matching.
 aho-corasick = "0.6.0"
@@ -27,17 +30,17 @@ thread_local = "0.3.2"
 # For parsing regular expressions.
 regex-syntax = { path = "regex-syntax", version = "0.4.1" }
 # For accelerating text search.
-simd = { version = "0.1.1", optional = true }
+simd = { version = "0.2.1", optional = true }
 # For compiling UTF-8 decoding into automata.
 utf8-ranges = "1.0.0"
 
 [dev-dependencies]
 # For examples.
 lazy_static = "1"
 # For property based tests.
-quickcheck = { version = "0.5", default-features = false }
+quickcheck = { version = "0.6", default-features = false }
 # For generating random test data.
-rand = "0.3.15"
+rand = "0.4"
 
 [features]
 # Enable to use the unstable pattern traits defined in std.
@@ -94,5 +97,11 @@ name = "backtrack-utf8bytes"
 path = "tests/test_backtrack_bytes.rs"
 name = "backtrack-bytes"
 
+[profile.release]
+debug = true
+
+[profile.bench]
+debug = true
+
 [profile.test]
 debug = true

HACKING.md

@@ -185,37 +185,36 @@ A regular expression program is essentially a sequence of opcodes produced by
 the compiler plus various facts about the regular expression (such as whether
 it is anchored, its capture names, etc.).
 
-### The regex! macro (or why `regex::internal` exists)
-
-The `regex!` macro is defined in the `regex_macros` crate as a compiler plugin,
-which is maintained in this repository. The `regex!` macro compiles a regular
-expression at compile time into specialized Rust code.
-
-The `regex!` macro was written when this library was first conceived and
-unfortunately hasn't changed much since then. In particular, it encodes the
-entire Pike VM into stack allocated space (no heap allocation is done). When
-`regex!` was first written, this provided a substantial speed boost over
-so-called "dynamic" regexes compiled at runtime, and in particular had much
-lower overhead per match. This was because the only matching engine at the
-time was the Pike VM. The addition of other matching engines has inverted
-the relationship; the `regex!` macro is almost never faster than the dynamic
-variant. (In fact, it is typically substantially slower.)
-
-In order to build the `regex!` macro this way, it must have access to some
-internals of the regex library, which is in a distinct crate. (Compiler plugins
-must be part of a distinct crate.) Namely, it must be able to compile a regular
-expression and access its opcodes. The necessary internals are exported as part
-of the top-level `internal` module in the regex library, but is hidden from
-public documentation. In order to present a uniform API between programs build
-by the `regex!` macro and their dynamic analoges, the `Regex` type is an enum
-whose variants are hidden from public documentation.
-
-In the future, the `regex!` macro should probably work more like Ragel, but
-it's not clear how hard this is. In particular, the `regex!` macro should be
-able to support all the features of dynamic regexes, which may be hard to do
-with a Ragel-style implementation approach. (Which somewhat suggests that the
-`regex!` macro may also need to grow conditional execution logic like the
-dynamic variants, which seems rather grotesque.)
+### The regex! macro
+
+The `regex!` macro no longer exists. It was developed in a bygone era as a
+compiler plugin during the infancy of the regex crate. Back then, then only
+matching engine in the crate was the Pike VM. The `regex!` macro was, itself,
+also a Pike VM. The only advantages it offered over the dynamic Pike VM that
+was built at runtime were the following:
+
+  1. Syntax checking was done at compile time. Your Rust program wouldn't
+     compile if your regex didn't compile.
+  2. Reduction of overhead that was proportional to the size of the regex.
+     For the most part, this overhead consisted of heap allocation, which
+     was nearly eliminated in the compiler plugin.
+
+The main takeaway here is that the compiler plugin was a marginally faster
+version of a slow regex engine. As the regex crate evolved, it grew other regex
+engines (DFA, bounded backtracker) and sophisticated literal optimizations.
+The regex macro didn't keep pace, and it therefore became (dramatically) slower
+than the dynamic engines. The only reason left to use it was for the compile
+time guarantee that your regex is correct. Fortunately, Clippy (the Rust lint
+tool) has a lint that checks your regular expression validity, which mostly
+replaces that use case.
+
+Additionally, the regex compiler plugin stopped receiving maintenance. Nobody
+complained. At that point, it seemed prudent to just remove it.
+
+Will a compiler plugin be brought back? The future is murky, but there is
+definitely an opportunity there to build something that is faster than the
+dynamic engines in some cases. But it will be challenging! As of now, there
+are no plans to work on this.
 
 
 ## Testing
@@ -236,7 +235,6 @@ the AT&T test suite) and code generate tests for each matching engine. The
 approach we use in this library is to create a Cargo.toml entry point for each
 matching engine we want to test. The entry points are:
 
-* `tests/test_plugin.rs` - tests the `regex!` macro
 * `tests/test_default.rs` - tests `Regex::new`
 * `tests/test_default_bytes.rs` - tests `bytes::Regex::new`
 * `tests/test_nfa.rs` - tests `Regex::new`, forced to use the NFA
@@ -261,18 +259,14 @@ entry points, it can take a while to compile everything. To reduce compile
 times slightly, try using `cargo test --test default`, which will only use the
 `tests/test_default.rs` entry point.
 
-N.B. To run tests for the `regex!` macro, use:
-
-    cargo test --manifest-path regex_macros/Cargo.toml
-
 
 ## Benchmarking
 
 The benchmarking in this crate is made up of many micro-benchmarks. Currently,
 there are two primary sets of benchmarks: the benchmarks that were adopted
-at this library's inception (in `benches/src/misc.rs`) and a newer set of
+at this library's inception (in `bench/src/misc.rs`) and a newer set of
 benchmarks meant to test various optimizations. Specifically, the latter set
-contain some analysis and are in `benches/src/sherlock.rs`. Also, the latter
+contain some analysis and are in `bench/src/sherlock.rs`. Also, the latter
 set are all executed on the same lengthy input whereas the former benchmarks
 are executed on strings of varying length.
 
@@ -284,7 +278,6 @@ separately from the main regex crate.
 Benchmarking follows a similarly wonky setup as tests. There are multiple entry
 points:
 
-* `bench_rust_plugin.rs` - benchmarks the `regex!` macro
 * `bench_rust.rs` - benchmarks `Regex::new`
 * `bench_rust_bytes.rs` benchmarks `bytes::Regex::new`
 * `bench_pcre.rs` - benchmarks PCRE
@@ -299,36 +292,36 @@ library benchmarks (especially RE2).
 If you're hacking on one of the matching engines and just want to see
 benchmarks, then all you need to run is:
 
-    $ ./run-bench rust
+    $ ./bench/run rust
 
 If you want to compare your results with older benchmarks, then try:
 
-    $ ./run-bench rust | tee old
+    $ ./bench/run rust | tee old
     $ ... make it faster
-    $ ./run-bench rust | tee new
-    $ cargo-benchcmp old new --improvements
+    $ ./bench/run rust | tee new
+    $ cargo benchcmp old new --improvements
 
 The `cargo-benchcmp` utility is available here:
 https://github.com/BurntSushi/cargo-benchcmp
 
-The `run-bench` utility can run benchmarks for PCRE and Oniguruma too. See
-`./run-bench --help`.
+The `./bench/run` utility can run benchmarks for PCRE and Oniguruma too. See
+`./bench/bench --help`.
 
 ## Dev Docs
 
 When digging your teeth into the codebase for the first time, the
 crate documentation can be a great resource. By default `rustdoc`
 will strip out all documentation of private crate members in an
 effort to help consumers of the crate focus on the *interface*
-without having to concern themselves with the *implimentation*.
+without having to concern themselves with the *implementation*.
 Normally this is a great thing, but if you want to start hacking
 on regex internals it is not what you want. Many of the private members
 of this crate are well documented with rustdoc style comments, and
 it would be a shame to miss out on the opportunity that presents.
 You can generate the private docs with:
 
 ```
-> rustdoc --crate-name docs src/lib.rs -o target/doc -L target/debug/deps --no-defaults --passes collapse-docs --passes unindent-comments
+$ rustdoc --crate-name docs src/lib.rs -o target/doc -L target/debug/deps --no-defaults --passes collapse-docs --passes unindent-comments
 ```
 
 Then just point your browser at `target/doc/regex/index.html`.

PERFORMANCE.md

@@ -2,7 +2,7 @@ Your friendly guide to understanding the performance characteristics of this
 crate.
 
 This guide assumes some familiarity with the public API of this crate, which
-can be found here: http://doc.rust-lang.org/regex/regex/index.html
+can be found here: https://docs.rs/regex
 
 ## Theory vs. Practice
 

README.md

@@ -14,13 +14,13 @@ by [RE2](https://github.com/google/re2).
 
 ### Documentation
 
-[Module documentation with examples](https://doc.rust-lang.org/regex).
+[Module documentation with examples](https://docs.rs/regex).
 The module documentation also include a comprehensive description of the syntax
 supported.
 
 Documentation with examples for the various matching functions and iterators
 can be found on the
-[`Regex` type](https://doc.rust-lang.org/regex/regex/struct.Regex.html).
+[`Regex` type](https://docs.rs/regex/*/regex/struct.Regex.html).
 
 ### Usage
 
@@ -188,37 +188,6 @@ assert!(!matches.matched(5));
 assert!(matches.matched(6));
 ```
 
-### Usage: `regex!` compiler plugin
-
-**WARNING**: The `regex!` compiler plugin is orders of magnitude slower than
-the normal `Regex::new(...)` usage. You should not use the compiler plugin
-unless you have a very special reason for doing so. The performance difference
-may be the temporary, but the path forward at this point isn't clear.
-
-The `regex!` compiler plugin will compile your regexes at compile time. **This
-only works with a nightly compiler.**
-
-Here is a small example:
-
-```rust
-#![feature(plugin)]
-
-#![plugin(regex_macros)]
-extern crate regex;
-
-fn main() {
-    let re = regex!(r"(\d{4})-(\d{2})-(\d{2})");
-    let caps = re.captures("2010-03-14").unwrap();
-
-    assert_eq!("2010", caps[1]);
-    assert_eq!("03", caps[2]);
-    assert_eq!("14", caps[3]);
-}
-```
-
-Notice that we never `unwrap` the result of `regex!`. This is because your
-*program* won't compile if the regex doesn't compile. (Try `regex!("(")`.)
-
 
 ### Usage: a regular expression parser
 
@@ -228,8 +197,7 @@ execution. This may be useful if you're implementing your own regex engine or
 otherwise need to do analysis on the syntax of a regular expression. It is
 otherwise not recommended for general use.
 
-[Documentation for `regex-syntax` with
-examples](https://doc.rust-lang.org/regex/regex_syntax/index.html).
+[Documentation for `regex-syntax` with examples](https://docs.rs/regex-syntax).
 
 # License
 

appveyor.yml

@@ -10,8 +10,9 @@ install:
   - SET PATH=%PATH%;C:\MinGW\bin
   - rustc -V
   - cargo -V
-
 build: false
-
 test_script:
   - cargo test --verbose --jobs 4
+branches:
+  only:
+    - master

bench/Cargo.toml

@@ -5,26 +5,27 @@ version = "0.1.0"
 authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/rust-lang/regex"
-documentation = "http://doc.rust-lang.org/regex/regex/index.html"
+documentation = "https://docs.rs/regex"
 homepage = "https://github.com/rust-lang/regex"
 description = "Regex benchmarks for Rust's and other engines."
 build = "build.rs"
+workspace = ".."
 
 [dependencies]
-docopt = "0.6"
-lazy_static = "0.1"
+docopt = "0.8"
+lazy_static = "1"
 libc = "0.2"
-onig = { version = "1.2", optional = true }
+onig = { version = "3", optional = true }
 libpcre-sys = { version = "0.2", optional = true }
 memmap = "0.2"
 regex = { version = "0.2.0", path = "..", features = ["simd-accel"] }
-regex_macros = { version = "0.2.0", path = "../regex_macros", optional = true }
 regex-syntax = { version = "0.4.0", path = "../regex-syntax" }
-rustc-serialize = "0.3"
+serde = "1"
+serde_derive = "1"
 
 [build-dependencies]
-gcc = "0.3"
-pkg-config = "0.3"
+cc = "1"
+pkg-config = "0.3.9"
 
 [[bin]]
 name = "regex-run-one"
@@ -40,29 +41,18 @@ bench = false
 # Doing anything else will probably result in weird "duplicate definition"
 # compiler errors.
 #
-# Tip: use the run-bench script in the root of this repository to run
-# benchmarks.
+# Tip: use the `bench/run` script (in this directory) to run benchmarks.
 [features]
 re-pcre1 = ["libpcre-sys"]
 re-pcre2 = []
 re-onig = ["onig"]
 re-re2 = []
 re-rust = []
 re-rust-bytes = []
-re-rust-plugin = ["regex_macros"]
 re-tcl = []
 
 [[bench]]
 name = "bench"
 path = "src/bench.rs"
 test = false
 bench = true
-
-[profile.release]
-debug = true
-
-[profile.bench]
-debug = true
-
-[profile.test]
-debug = true