Auto merge of #33588 - nikomatsakis:compiletest-ui, r=acrichto

add UI testing framework

This adds a framework for capturing and tracking the precise output of rustc, which allows us to check all manner of minor details with the output. It's pretty strict right now -- the output must match almost exactly -- and hence maybe a bit too strict. But I figure we can add wildcards or whatever later. There is also a script intended to make updating the references easy, though the script could make things a *bit* easier (in particular, it'd be nice if it would find the build directory for you automatically).

One thing I was wondering about is the best way to test colors. Since windows doesn't embed those in the output stream, this test framework can't test colors on windows -- so I figure we can just write tests that are ignored on windows and which pass `--color=always` or whatever to rustc.

cc @jonathandturner
r? @alexcrichton

mk/tests.mk

@@ -274,6 +274,7 @@ check-stage$(1)-T-$(2)-H-$(3)-exec: \
 	check-stage$(1)-T-$(2)-H-$(3)-debuginfo-gdb-exec \
 	check-stage$(1)-T-$(2)-H-$(3)-debuginfo-lldb-exec \
 	check-stage$(1)-T-$(2)-H-$(3)-incremental-exec \
+	check-stage$(1)-T-$(2)-H-$(3)-ui-exec \
 	check-stage$(1)-T-$(2)-H-$(3)-doc-exec \
 	check-stage$(1)-T-$(2)-H-$(3)-pretty-exec
 
@@ -452,6 +453,9 @@ CODEGEN_CC := $(call rwildcard,$(S)src/test/codegen/,*.cc)
 CODEGEN_UNITS_RS := $(call rwildcard,$(S)src/test/codegen-units/,*.rs)
 INCREMENTAL_RS := $(call rwildcard,$(S)src/test/incremental/,*.rs)
 RMAKE_RS := $(wildcard $(S)src/test/run-make/*/Makefile)
+UI_RS := $(call rwildcard,$(S)src/test/ui/,*.rs) \
+         $(call rwildcard,$(S)src/test/ui/,*.stdout) \
+         $(call rwildcard,$(S)src/test/ui/,*.stderr)
 RUSTDOCCK_RS := $(call rwildcard,$(S)src/test/rustdoc/,*.rs)
 
 RPASS_TESTS := $(RPASS_RS)
@@ -469,6 +473,7 @@ CODEGEN_TESTS := $(CODEGEN_RS) $(CODEGEN_CC)
 CODEGEN_UNITS_TESTS := $(CODEGEN_UNITS_RS)
 INCREMENTAL_TESTS := $(INCREMENTAL_RS)
 RMAKE_TESTS := $(RMAKE_RS)
+UI_TESTS := $(UI_RS)
 RUSTDOCCK_TESTS := $(RUSTDOCCK_RS)
 
 CTEST_SRC_BASE_rpass = run-pass
@@ -541,6 +546,11 @@ CTEST_BUILD_BASE_rmake = run-make
 CTEST_MODE_rmake = run-make
 CTEST_RUNTOOL_rmake = $(CTEST_RUNTOOL)
 
+CTEST_SRC_BASE_ui = ui
+CTEST_BUILD_BASE_ui = ui
+CTEST_MODE_ui = ui
+CTEST_RUNTOOL_ui = $(CTEST_RUNTOOL)
+
 CTEST_SRC_BASE_rustdocck = rustdoc
 CTEST_BUILD_BASE_rustdocck = rustdoc
 CTEST_MODE_rustdocck = rustdoc
@@ -672,7 +682,7 @@ CTEST_DEPS_codegen-units_$(1)-T-$(2)-H-$(3) = $$(CODEGEN_UNITS_TESTS)
 CTEST_DEPS_incremental_$(1)-T-$(2)-H-$(3) = $$(INCREMENTAL_TESTS)
 CTEST_DEPS_rmake_$(1)-T-$(2)-H-$(3) = $$(RMAKE_TESTS) \
 	$$(CSREQ$(1)_T_$(3)_H_$(3)) $$(SREQ$(1)_T_$(2)_H_$(3))
-
+CTEST_DEPS_ui_$(1)-T-$(2)-H-$(3) = $$(UI_TESTS)
 CTEST_DEPS_rustdocck_$(1)-T-$(2)-H-$(3) = $$(RUSTDOCCK_TESTS) \
 		$$(HBIN$(1)_H_$(3))/rustdoc$$(X_$(3)) \
 		$(S)src/etc/htmldocck.py
@@ -744,7 +754,7 @@ endef
 
 CTEST_NAMES = rpass rpass-valgrind rpass-full rfail-full cfail-full rfail cfail pfail \
 	debuginfo-gdb debuginfo-lldb codegen codegen-units rustdocck incremental \
-	rmake
+	rmake ui
 
 $(foreach host,$(CFG_HOST), \
  $(eval $(foreach target,$(CFG_TARGET), \
@@ -943,6 +953,7 @@ TEST_GROUPS = \
 	codegen \
 	codegen-units \
 	incremental \
+	ui \
 	doc \
 	$(foreach docname,$(DOC_NAMES),doc-$(docname)) \
 	pretty \

src/bootstrap/build/mod.rs

@@ -342,6 +342,14 @@ impl Build {
                     check::compiletest(self, &compiler, target.target,
                                        "codegen-units", "codegen-units");
                 }
+                CheckIncremental { compiler } => {
+                    check::compiletest(self, &compiler, target.target,
+                                       "incremental", "incremental");
+                }
+                CheckUi { compiler } => {
+                    check::compiletest(self, &compiler, target.target,
+                                       "ui", "ui");
+                }
                 CheckDebuginfo { compiler } => {
                     if target.target.contains("msvc") ||
                        target.target.contains("android") {

src/bootstrap/build/step.rs

@@ -111,6 +111,8 @@ macro_rules! targets {
             (check_pfail, CheckPFail { compiler: Compiler<'a> }),
             (check_codegen, CheckCodegen { compiler: Compiler<'a> }),
             (check_codegen_units, CheckCodegenUnits { compiler: Compiler<'a> }),
+            (check_incremental, CheckIncremental { compiler: Compiler<'a> }),
+            (check_ui, CheckUi { compiler: Compiler<'a> }),
             (check_debuginfo, CheckDebuginfo { compiler: Compiler<'a> }),
             (check_rustdoc, CheckRustdoc { compiler: Compiler<'a> }),
             (check_pretty, CheckPretty { compiler: Compiler<'a> }),
@@ -379,6 +381,8 @@ impl<'a> Step<'a> {
                     self.check_cfail(compiler),
                     self.check_rfail(compiler),
                     self.check_pfail(compiler),
+                    self.check_incremental(compiler),
+                    self.check_ui(compiler),
                     self.check_crate_std(compiler),
                     self.check_crate_test(compiler),
                     self.check_crate_rustc(compiler),
@@ -412,6 +416,8 @@ impl<'a> Step<'a> {
             Source::CheckPFail { compiler } |
             Source::CheckCodegen { compiler } |
             Source::CheckCodegenUnits { compiler } |
+            Source::CheckIncremental { compiler } |
+            Source::CheckUi { compiler } |
             Source::CheckRustdoc { compiler } |
             Source::CheckPretty { compiler } |
             Source::CheckCFail { compiler } |

src/test/ui/README.md

@@ -0,0 +1,31 @@
+# Guide to the UI Tests
+
+The UI tests are intended to capture the compiler's complete output,
+so that we can test all aspects of the presentation. They work by
+compiling a file (e.g., `hello_world/main.rs`), capturing the output,
+and then applying some normalization (see below). This normalized
+result is then compared against reference files named
+`hello_world/main.stderr` and `hello_world/main.stdout`. If either of
+those files doesn't exist, the output must be empty. If the test run
+fails, we will print out the current output, but it is also saved in
+`build/<target-triple>/test/ui/hello_world/main.stdout` (this path is
+printed as part of the test failure mesage), so you can run `diff` and
+so forth.
+
+# Editing and updating the reference files
+
+If you have changed the compiler's output intentionally, or you are
+making a new test, you can use the script `update-references.sh` to
+update the references. When you run the test framework, it will report
+various errors: in those errors is a command you can use to run the
+`update-references.sh` script, which will then copy over the files
+from the build directory and use them as the new reference. You can
+also just run `update-all-references.sh`. In both cases, you can run
+the script with `--help` to get a help message.
+
+# Normalization
+
+The normalization applied is aimed at filenames:
+
+- the test directory is replaced with `$DIR`
+- all backslashes (\) are converted to forward slashes (/) (for windows)

src/test/ui/hello_world/main.rs

@@ -0,0 +1,15 @@
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Test that compiling hello world succeeds with no output of any kind.
+
+fn main() {
+    println!("Hello, world!");
+}

src/test/ui/mismatched_types/main.rs

@@ -0,0 +1,17 @@
+// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// rustc-env:RUST_NEW_ERROR_FORMAT
+
+fn main() {
+    let x: u32 = (
+    );
+}
+

src/test/ui/mismatched_types/main.stderr

@@ -0,0 +1,8 @@
+error: mismatched types [--explain E0308]
+  --> $DIR/main.rs:14:18
+14 |>     let x: u32 = (
+   |>                  ^ expected u32, found ()
+note: expected type `u32`
+note:    found type `()`
+
+error: aborting due to previous error

src/test/ui/update-all-references.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+#
+# Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+# A script to update the references for all tests. The idea is that
+# you do a run, which will generate files in the build directory
+# containing the (normalized) actual output of the compiler. You then
+# run this script, which will copy those files over. If you find
+# yourself manually editing a foo.stderr file, you're doing it wrong.
+#
+# See all `update-references.sh`, if you just want to update a single test.
+
+if [[ "$1" == "--help" || "$1" == "-h" || "$1" == "" || "$2" != "" ]]; then
+    echo "usage: $0 <build-directory>"
+    echo ""
+    echo "For example:"
+    echo "   $0 ../../../build/x86_64-apple-darwin/test/ui"
+fi
+
+BUILD_DIR=$PWD/$1
+MY_DIR=$(dirname $0)
+cd $MY_DIR
+find . -name '*.rs' | xargs ./update-references.sh $BUILD_DIR

src/test/ui/update-references.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+#
+# Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+# A script to update the references for particular tests. The idea is
+# that you do a run, which will generate files in the build directory
+# containing the (normalized) actual output of the compiler. This
+# script will then copy that output and replace the "expected output"
+# files. You can then commit the changes.
+#
+# If you find yourself manually editing a foo.stderr file, you're
+# doing it wrong.
+
+if [[ "$1" == "--help" || "$1" == "-h" || "$1" == "" || "$2" == "" ]]; then
+    echo "usage: $0 <build-directory> <relative-path-to-rs-files>"
+    echo ""
+    echo "For example:"
+    echo "   $0 ../../../build/x86_64-apple-darwin/test/ui *.rs */*.rs"
+fi
+
+MYDIR=$(dirname $0)
+
+BUILD_DIR="$1"
+shift
+
+while [[ "$1" != "" ]]; do
+    STDERR_NAME="${1/%.rs/.stderr}"
+    STDOUT_NAME="${1/%.rs/.stdout}"
+    shift
+    if [ -f $BUILD_DIR/$STDOUT_NAME ] && \
+           ! (diff $BUILD_DIR/$STDOUT_NAME $MYDIR/$STDOUT_NAME > /dev/null); then
+        echo updating $MYDIR/$STDOUT_NAME
+        cp $BUILD_DIR/$STDOUT_NAME $MYDIR/$STDOUT_NAME
+    fi
+    if [ -f $BUILD_DIR/$STDERR_NAME ] && \
+           ! (diff $BUILD_DIR/$STDERR_NAME $MYDIR/$STDERR_NAME > /dev/null); then
+        echo updating $MYDIR/$STDERR_NAME
+        cp $BUILD_DIR/$STDERR_NAME $MYDIR/$STDERR_NAME
+    fi
+done
+
+

src/tools/compiletest/src/common.rs

@@ -28,6 +28,7 @@ pub enum Mode {
     CodegenUnits,
     Incremental,
     RunMake,
+    Ui,
 }
 
 impl FromStr for Mode {
@@ -47,6 +48,7 @@ impl FromStr for Mode {
           "codegen-units" => Ok(CodegenUnits),
           "incremental" => Ok(Incremental),
           "run-make" => Ok(RunMake),
+          "ui" => Ok(Ui),
           _ => Err(()),
         }
     }
@@ -68,6 +70,7 @@ impl fmt::Display for Mode {
             CodegenUnits => "codegen-units",
             Incremental => "incremental",
             RunMake => "run-make",
+            Ui => "ui",
         }, f)
     }
 }

src/tools/compiletest/src/main.rs

@@ -50,6 +50,7 @@ pub mod runtest;
 pub mod common;
 pub mod errors;
 mod raise_fd_limit;
+mod uidiff;
 
 fn main() {
     #[cfg(cargobuild)]