Merge branch 'ml/userdiff-rust'

The pattern "git diff/grep" use to extract funcname and words
boundary for Rust has been added.

* ml/userdiff-rust:
  userdiff: two simplifications of patterns for rust
  userdiff: add built-in pattern for rust

Author: gitster

Documentation/gitattributes.txt

@@ -833,6 +833,8 @@ patterns are available:
 
 - `ruby` suitable for source code in the Ruby language.
 
+- `rust` suitable for source code in the Rust language.
+
 - `tex` suitable for source code for LaTeX documents.
 
 

t/t4018-diff-funcname.sh

@@ -43,6 +43,7 @@ diffpatterns="
 	php
 	python
 	ruby
+	rust
 	tex
 	custom1
 	custom2

t/t4018/rust-fn

@@ -0,0 +1,5 @@
+pub(self) fn RIGHT<T>(x: &[T]) where T: Debug {
+    let _ = x;
+    // a comment
+    let a = ChangeMe;
+}

t/t4018/rust-impl

@@ -0,0 +1,5 @@
+impl<'a, T: AsRef<[u8]>>  std::RIGHT for Git<'a> {
+
+    pub fn ChangeMe(&self) -> () {
+    }
+}

t/t4018/rust-struct

@@ -0,0 +1,5 @@
+#[derive(Debug)]
+pub(super) struct RIGHT<'a> {
+    name: &'a str,
+    age: ChangeMe,
+}

t/t4018/rust-trait

@@ -0,0 +1,5 @@
+unsafe trait RIGHT<T> {
+    fn len(&self) -> u32;
+    fn ChangeMe(&self, n: u32) -> T;
+    fn iter<F>(&self, f: F) where F: Fn(T);
+}

userdiff.c

@@ -135,6 +135,12 @@ PATTERNS("ruby", "^[ \t]*((class|module|def)[ \t].*)$",
 	 "(@|@@|\\$)?[a-zA-Z_][a-zA-Z0-9_]*"
 	 "|[-+0-9.e]+|0[xXbB]?[0-9a-fA-F]+|\\?(\\\\C-)?(\\\\M-)?."
 	 "|//=?|[-+*/<>%&^|=!]=|<<=?|>>=?|===|\\.{1,3}|::|[!=]~"),
+PATTERNS("rust",
+	 "^[\t ]*((pub(\\([^\\)]+\\))?[\t ]+)?((async|const|unsafe|extern([\t ]+\"[^\"]+\"))[\t ]+)?(struct|enum|union|mod|trait|fn|impl)[< \t]+[^;]*)$",
+	 /* -- */
+	 "[a-zA-Z_][a-zA-Z0-9_]*"
+	 "|[0-9][0-9_a-fA-Fiosuxz]*(\\.([0-9]*[eE][+-]?)?[0-9_fF]*)?"
+	 "|[-+*\\/<>%&^|=!:]=|<<=?|>>=?|&&|\\|\\||->|=>|\\.{2}=|\\.{3}|::"),
 PATTERNS("bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
 	 "[={}\"]|[^={}\" \t]+"),
 PATTERNS("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",