Enable or disable colored output according to CLICOLOR(_FORCE)

src/libsyntax/errors/emitter.rs

@@ -17,7 +17,7 @@ use errors::{Level, RenderSpan, DiagnosticBuilder};
 use errors::RenderSpan::*;
 use errors::Level::*;
 
-use std::{cmp, fmt};
+use std::{cmp, fmt, env};
 use std::io::prelude::*;
 use std::io;
 use std::rc::Rc;
@@ -55,7 +55,8 @@ impl ColorConfig {
         match *self {
             ColorConfig::Always => true,
             ColorConfig::Never  => false,
-            ColorConfig::Auto   => stderr_isatty(),
+            ColorConfig::Auto   => env::var("CLICOLOR_FORCE").unwrap_or("0".to_string()) != "0" ||
+                      (stderr_isatty() && env::var("CLICOLOR").unwrap_or("1".to_string()) != "0"),
         }
     }
 }

src/libterm/terminfo/mod.rs

@@ -24,7 +24,7 @@ use Attr;
 use color;
 use Terminal;
 use self::searcher::get_dbpath_for_term;
-use self::parser::compiled::{parse, msys_terminfo};
+use self::parser::compiled::{parse, ansi_terminfo};
 use self::parm::{expand, Variables, Param};
 
 
@@ -81,14 +81,18 @@ impl fmt::Display for Error {
 impl TermInfo {
     /// Create a TermInfo based on current environment.
     pub fn from_env() -> Result<TermInfo, Error> {
+        if env::var("CLICOLOR_FORCE").unwrap_or("0".to_string()) != "0" {
+            return Ok(ansi_terminfo());
+        }
         let term = match env::var("TERM") {
             Ok(name) => TermInfo::from_name(&name),
             Err(..) => return Err(Error::TermUnset),
         };
 
-        if term.is_err() && env::var("MSYSCON").ok().map_or(false, |s| "mintty.exe" == s) {
+        if term.is_err() && (env::var("MSYSCON").ok().map_or(false, |s| "mintty.exe" == s) ||
+           env::var("CLICOLOR").unwrap_or("0".to_string()) != "0") {
             // msys terminal
-            Ok(msys_terminfo())
+            Ok(ansi_terminfo())
         } else {
             term
         }

src/libterm/terminfo/parser/compiled.rs

@@ -323,8 +323,9 @@ pub fn parse(file: &mut io::Read, longnames: bool) -> Result<TermInfo, String> {
     })
 }
 
-/// Create a dummy TermInfo struct for msys terminals
-pub fn msys_terminfo() -> TermInfo {
+/// Create a dummy TermInfo struct which only supports ISO 6429 (ANSI) color sequences. This is
+/// used for msys and when CLICOLOR(_FORCE) is set.
+pub fn ansi_terminfo() -> TermInfo {
     let mut strings = HashMap::new();
     strings.insert("sgr0".to_string(), b"\x1B[0m".to_vec());
     strings.insert("bold".to_string(), b"\x1B[1m".to_vec());