Documentation: more gn, less gyp

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4698
NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=4698

Change-Id: I03100542752a769060a7f0c9671cc44acbea2e48
Reviewed-on: https://skia-review.googlesource.com/4698
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Hal Canary <halcanary@google.com>

6 files changed, 81 insertions, 135 deletions

diff --git a/site/dev/contrib/submit.md b/site/dev/contrib/submit.md
index c01ec0ff49..a64fe87fa3 100644
--- a/site/dev/contrib/submit.md
+++ b/site/dev/contrib/submit.md
@@ -32,7 +32,7 @@ If your branch gets out of date, you will need to update it:
 <!--?prettify lang=sh?-->
 
     git pull
-    python bin/sync-and-gyp
+    python bin/sync
 
 Adding a unit test
 ------------------
diff --git a/site/dev/design/sync-and-gyp.md b/site/dev/design/sync-and-gyp.md
deleted file mode 100644
index 894ad9a5c0..0000000000
--- a/site/dev/design/sync-and-gyp.md
+++ /dev/null
@@ -1,24 +0,0 @@
-sync-and-gyp
-============
-
-[`sync-and-gyp`](https://skia.googlesource.com/skia.git/+/master/bin/sync-and-gyp)
-is a Python program that wraps `gclient sync` and `gyp_skia`.
-Motivations for using it:
-
--  Fewer steps to configure and compile Skia and Skia's dependencies.
-   This makes documentation cleaner, too.
-
--  Written in Python, so it will work on all platforms.  Python is
-   already necessary for gyp.
-
--  Sets up gclient better than `gclient config`, which has been broken.
-
--  Checks to see if the `DEPS` file has changed since it last ran
-   `gclient sync`.  If not, it skips that step.
-
--  Checks to see if gyp needs to be re-run (it checks environment
-   variables and changed or added files); if not, it skips running
-   `gyp_skia`.
-
--  Since running `sync-and-gyp` is fast when it can do nothing, it is
-   easy to do before every recompile of Skia.  This is a good habit.
diff --git a/site/dev/design/sync.md b/site/dev/design/sync.md
new file mode 100644
index 0000000000..d7c192fdbc
--- /dev/null
+++ b/site/dev/design/sync.md
@@ -0,0 +1,18 @@
+sync
+====
+
+[`sync`](https://skia.googlesource.com/skia.git/+/master/bin/sync)
+is a Python program that wraps `gclient sync` and `fetch-gn`.
+Motivations for using it:
+
+-  Written in Python, so it will work on all platforms.
+
+-  Sets up gclient better than `gclient config`, which has been broken.
+
+-  Checks to see if the `DEPS` file has changed since it last ran
+   `gclient sync`.  If not, it skips that step.
+
+-  Calls `fetch-gn` if needed.
+
+-  Since running `sync` is fast when it can do nothing, it is
+   easy to do before every recompile of Skia.  This is a good habit.
diff --git a/site/dev/testing/testing.md b/site/dev/testing/testing.md
index e577a51231..29f7a4dae0 100644
--- a/site/dev/testing/testing.md
+++ b/site/dev/testing/testing.md
@@ -4,11 +4,12 @@ Correctness Testing
 Skia correctness testing is primarily served by a tool named DM.
 This is a quickstart to building and running DM.
 
-~~~
-$ python bin/sync-and-gyp
-$ ninja -C out/Debug dm
-$ out/Debug/dm -v -w dm_output
-~~~
+<!--?prettify lang=sh?-->
+
+    python bin/sync
+    gn gen out/Debug
+    ninja -C out/Debug dm
+    out/Debug/dm -v -w dm_output
 
 When you run this, you may notice your CPU peg to 100% for a while, then taper
 off to 1 or 2 active cores as the run finishes.  This is intentional.  DM is
@@ -145,46 +146,47 @@ they happen and then again all together after everything is done running.
 These failures are also included in the dm.json file.
 
 DM has a simple facility to compare against the results of a previous run:
-~~~
-$ python bin/sync-and-gyp
-$ ninja -C out/Debug dm
-$ out/Debug/dm -w good
 
-  # do some work
+<!--?prettify lang=sh?-->
+
+    ninja -C out/Debug dm
+    out/Debug/dm -w good
+
+    # do some work
+
+    ninja -C out/Debug dm
+    out/Debug/dm -r good -w bad
 
-$ python bin/sync-and-gyp
-$ ninja -C out/Debug dm
-$ out/Debug/dm -r good -w bad
-~~~
 When using `-r`, DM will display a failure for any test that didn't produce the
 same image as the `good` run.
 
 For anything fancier, I suggest using skdiff:
-~~~
-$ python bin/sync-and-gyp
-$ ninja -C out/Debug dm
-$ out/Debug/dm -w good
 
-  # do some work
+<!--?prettify lang=sh?-->
 
-$ python bin/sync-and-gyp
-$ ninja -C out/Debug dm
-$ out/Debug/dm -w bad
+    ninja -C out/Debug dm
+    out/Debug/dm -w good
 
-$ ninja -C out/Debug skdiff
-$ mkdir diff
-$ out/Debug/skdiff good bad diff
+    # do some work
 
-  # open diff/index.html in your web browser
-~~~
+    ninja -C out/Debug dm
+    out/Debug/dm -w bad
+
+    ninja -C out/Debug skdiff
+    mkdir diff
+    out/Debug/skdiff good bad diff
+
+    # open diff/index.html in your web browser
 
 That's the basics of DM.  DM supports many other modes and flags.  Here are a
 few examples you might find handy.
-~~~
-$ out/Debug/dm --help        # Print all flags, their defaults, and a brief explanation of each.
-$ out/Debug/dm --src tests   # Run only unit tests.
-$ out/Debug/dm --nocpu       # Test only GPU-backed work.
-$ out/Debug/dm --nogpu       # Test only CPU-backed work.
-$ out/Debug/dm --match blur  # Run only work with "blur" in its name.
-$ out/Debug/dm --dryRun      # Don't really do anything, just print out what we'd do.
-~~~
+
+<!--?prettify lang=sh?-->
+
+    out/Debug/dm --help        # Print all flags, their defaults, and a brief explanation of each.
+    out/Debug/dm --src tests   # Run only unit tests.
+    out/Debug/dm --nocpu       # Test only GPU-backed work.
+    out/Debug/dm --nogpu       # Test only CPU-backed work.
+    out/Debug/dm --match blur  # Run only work with "blur" in its name.
+    out/Debug/dm --dryRun      # Don't really do anything, just print out what we'd do.
+
diff --git a/site/dev/testing/tests.md b/site/dev/testing/tests.md
index 3b216e88af..701c2c4dfd 100644
--- a/site/dev/testing/tests.md
+++ b/site/dev/testing/tests.md
@@ -5,6 +5,14 @@ Writing Skia Tests
 +   [Rendering Tests](#gm)
 +   [Benchmark Tests](#bench)
 
+We assume you have already synced Skia's dependecies and set up Skia's build system.
+
+<!--?prettify lang=sh?-->
+
+    python bin/sync
+    gn gen out/Debug
+    gn gen out/Release --args='is_debug=false'
+
 <span id="test"></span>
 
 Writing a Unit Test
@@ -29,9 +37,12 @@ Writing a Unit Test
             REPORTER_ASSERT(reporter, lifeIsGood);
         }
 
-2.  Recompile and run test:
+2.  Add `NewUnitTest.cpp` to `gn/tests.gni`.
+
+3.  Recompile and run test:
+
+    <!--?prettify lang=sh?-->
 
-        python bin/sync-and-gyp
         ninja -C out/Debug dm
         out/Debug/dm --match NewUnitTest
 
@@ -58,22 +69,22 @@ Writing a Rendering Test
             canvas->drawLine(16, 16, 112, 112, p);
         }
 
-2.  Recompile and run test:
+2.  Add `newgmtest.cpp` to `gn/gm.gni`.
+
+3.  Recompile and run test:
+
+    <!--?prettify lang=sh?-->
 
-        python bin/sync-and-gyp
         ninja -C out/Debug dm
         out/Debug/dm --match newgmtest
 
-3.  Run the GM inside SampleApp:
+4.  Run the GM inside SampleApp:
+
+    <!--?prettify lang=sh?-->
 
-        python bin/sync-and-gyp
         ninja -C out/Debug SampleApp
         out/Debug/SampleApp --slide GM:newgmtest
 
-    On MacOS, try this:
-
-        out/Debug/SampleApp.app/Contents/MacOS/SampleApp --slide GM:newgmtest
-
 <span id="bench"></span>
 
 Writing a Benchmark Test
@@ -108,9 +119,11 @@ Writing a Benchmark Test
         }  // namespace
         DEF_BENCH(return new FooBench;)
 
+2.  Add `FooBench.cpp` to `gn/bench.gni`.
+
+3.  Recompile and run nanobench:
 
-2.  Recompile and run nanobench:
+    <!--?prettify lang=sh?-->
 
-        python bin/sync-and-gyp
         ninja -C out/Release nanobench
         out/Release/nanobench --match Foo
diff --git a/site/user/tips.md b/site/user/tips.md
index ec94db6260..c477138fc8 100644
--- a/site/user/tips.md
+++ b/site/user/tips.md
@@ -1,7 +1,6 @@
 Tips & FAQ
 ==========
 
-+   [Gyp Options](#gypdefines)
 +   [Bitmap Subsetting](#bitmap-subsetting)
 +   [Capture a `.skp` file on a web page in Chromium](#skp-capture)
 +   [Capture a `.mskp` file on a web page in Chromium](#mskp-capture)
@@ -12,68 +11,6 @@ Tips & FAQ
 
 * * *
 
-<span id="gypdefines">Gyp Options</span>
-----------------------------------------
-
-When running `sync-and-gyp`, the `GYP_DEFINES` environment variable can
-be used to change Skia’s compile-time settings, using a
-space-separated list of key=value pairs. For example, to disable both
-the Skia GPU backend and PDF backends, run it as follows:
-
-<!--?prettify lang=sh?-->
-
-    GYP_DEFINES='skia_gpu=0 skia_pdf=0' python bin/sync-and-gyp
-    ninja -C out/Debug
-
-Note: Setting enviroment variables in the Windows CMD.EXE shell [uses a
-different syntax](/user/quick/windows#env).
-
-You can also set environment variables such as `CC`, `CXX`,
-`CFLAGS`, `CXXFLAGS`, or `CPPFLAGS` to control how Skia is compiled.
-To build with clang, for example:
-
-<!--?prettify lang=sh?-->
-
-    CC='clang' CXX='clang++' python bin/sync-and-gyp
-    ninja -C out/Debug
-
-To build with clang and enable a compiler warning for unused parameters in C++
-(but not C or assembly) code:
-
-<!--?prettify lang=sh?-->
-
-    CXXFLAGS='-Wunused-parameter' \
-        CC='clang' CXX='clang++' python bin/sync-and-gyp
-    ninja -C out/Debug
-
-
-The `GYP_GENERATORS` environment variable can be used to set the
-build systems that you want to use (as a comma-separated list).
-The default is `'ninja,msvs-ninja'` on Windows, `'ninja,xcode'` on
-Mac OS X, and just `'ninja'` on Linux.  For example, to generate
-only Ninja files on Mac:
-
-<!--?prettify lang=sh?-->
-
-    GYP_GENERATORS='ninja' python bin/sync-and-gyp
-    ninja -C out/Debug
-
-Finally, the `SKIA_OUT` environment variable can be used to set
-the path for the build directory.  The default is `out` inside the
-top-level Skia source directory.  For example to test Skia with
-two different compilers:
-
-<!--?prettify lang=sh?-->
-
-    CC='clang' CXX='clang++' SKIA_OUT=~/build/skia_clang python bin/sync-and-gyp
-    CC='gcc'   CXX='g++'     SKIA_OUT=~/build/skia_gcc   python bin/sync-and-gyp
-    ninja -C ~/build/skia_clang/Debug
-    ninja -C ~/build/skia_gcc/Debug
-
-* * *
-
-
-
 <span id="bitmap-subsetting">Bitmap Subsetting</span>
 -----------------------------------------------------