doc: split contribute.html into code.html and contribute.html

R=r
https://golang.org/cl/170042

doc/code.html

+<!-- How to Write Go Code -->
+
+<h2 id="Introduction">Introduction</h2>
+
+<p>
+This document explains how to write a new package
+and how to test code.
+It assumes you have installed Go using the
+<a href="install.html">installation instructions</a>.
+</p>
+
+<p>
+Before embarking on a change to an existing
+package or the creation of a new package,
+it's a good idea to send mail to the <a href="http://groups.google.com/group/golang-nuts">mailing list</a>
+to let people know what you are thinking of doing.
+Doing so helps avoid duplication of effort and
+enables discussions about design before much code
+has been written.
+</p>
+
+<h2 id="Community_resources">Community resources</h2>
+
+<p>
+For real-time help, there may be users or developers on
+<code>#go-nuts</code> on the <a href="http://freenode.net/">Freenode</a> IRC server.
+</p>
+
+<p>
+The official mailing list for discussion of the Go language is
+<a href="http://groups.google.com/group/golang-nuts">Go Nuts</a>.
+</p>
+
+<p>
+Bugs can be reported using the <a href="http://code.google.com/p/go/issues/list">Go issue tracker</a>.
+</p>
+
+<p>
+For those who wish to keep up with development,
+there is another mailing list, <a href="http://groups.google.com/group/golang-checkins">golang-checkins</a>,
+that receives a message summarizing each checkin to the Go repository.
+</p>
+
+
+<h2 id="New_package">Creating a new package</h2>
+
+<p>
+The source code for the package with import path
+<code>x/y</code> is, by convention, kept in the
+directory <code>$GOROOT/src/pkg/x/y</code>.
+</p>
+
+<h3>Makefile</h3>
+
+<p>
+It would be nice to have Go-specific tools that
+inspect the source files to determine what to build and in
+what order, but for now, Go uses GNU <code>make</code>.
+Thus, the first file to create in a new package directory is
+usually the <code>Makefile</code>.
+The basic form used in the Go source tree
+is illustrated by <a href="../src/pkg/container/vector/Makefile"><code>src/pkg/container/vector/Makefile</code></a>:
+</p>
+
+<pre>
+include ../../../Make.$(GOARCH)
+
+TARG=container/vector
+GOFILES=\
+	intvector.go\
+	stringvector.go\
+	vector.go\
+
+include ../../../Make.pkg
+</pre>
+
+<p>
+Outside the Go source tree (for personal packages), the standard form is
+</p>
+
+<pre>
+include $(GOROOT)/src/Make.$(GOARCH)
+
+TARG=mypackage
+GOFILES=\
+	my1.go\
+	my2.go\
+
+include $(GOROOT)/src/Make.pkg
+</pre>
+
+<p>
+The first and last lines <code>include</code> standard definitions and rules.
+Packages maintained in the standard Go tree use a relative path (instead of
+<code>$(GOROOT)/src</code>) so that <code>make</code> will work correctly
+even if <code>$(GOROOT)</code> contains spaces.
+This makes it easy for programmers to try Go.
+</p>
+
+<p>
+<code>TARG</code> is the target install path for the package,
+the string that clients will use to import it.
+Inside the Go tree, this string should be the same as the directory
+in which the <code>Makefile</code> appears, with the
+<code>$GOROOT/src/pkg/</code> prefix removed.
+Outside the Go tree, you can use any <code>TARG</code> you
+want that doesn't conflict with the standard Go package names.
+A common convention is to use an identifying top-level name
+to group your packages: <code>myname/tree</code>, <code>myname/filter</code>, etc.
+Note that even if you keep your package source outside the
+Go tree, running <code>make install</code> installs your
+package binaries in the standard location&mdash;<code>$GOROOT/pkg</code>&mdash;to
+make it easy to find them.
+</p>
+
+<p>
+<code>GOFILES</code> is a list of source files to compile to
+create the package.  The trailing <code>\</code> characters
+allow the list to be split onto multiple lines
+for easy sorting.
+</p>
+
+<p>
+If you create a new package directory in the Go tree, add it to the list in
+<code>$GOROOT/src/pkg/Makefile</code> so that it
+is included in the standard build.  Then run:
+<pre>
+cd $GOROOT/src/pkg
+./deps.bash
+</pre>
+<p>
+to update the dependency file <code>Make.deps</code>.
+(This happens automatically each time you run <code>all.bash</code>
+or <code>make.bash</code>.)
+</p>
+
+<p>
+If you change the imports of an existing package,
+you do not need to edit <code>$GOROOT/src/pkg/Makefile</code>
+but you will still need to run <code>deps.bash</code> as above.
+</p>
+
+
+<h3>Go source files</h3>
+
+<p>
+The first statement in each of the source files listed in the <code>Makefile</code>
+should be <code>package <i>name</i></code>, where <code><i>name</i></code>
+is the package's default name for imports.
+(All files in a package must use the same <code><i>name</i></code>.)
+Go's convention is that the package name is the last element of the
+import path: the package imported as <code>"crypto/rot13"</code>
+should be named <code>rot13</code>.
+At the moment, the Go tools impose a restriction that package names are unique
+across all packages linked into a single binary, but that restriction
+will be lifted soon.
+</p>
+
+<p>
+Go compiles all the source files in a package at once, so one file
+can refer to constants, variables, types, and functions in another
+file without special arrangement or declarations.
+</p>
+
+<p>
+Writing clean, idiomatic Go code is beyond the scope of this document.
+<a href="effective_go.html">Effective Go</a> is an introduction to
+that topic.
+</p>
+
+<h2 id="Testing">Testing</h2>
+
+<p>
+Go has a lightweight test framework known as <code>gotest</code>.
+You write a test by creating a file with a name ending in <code>_test.go</code>
+that contains functions named <code>TestXXX</code> with signature <code>func (t *testing.T)</code>.
+The test framework runs each such function;
+if the function calls a failure function such as <code>t.Error</code> or <code>t.Fail</code>, the test is considered to have failed.
+The <a href="/cmd/gotest/">gotest command documentation</a>
+and the <a href="/pkg/testing/">testing package documentation</a> give more detail.
+</p>
+
+<p>
+The <code>*_test.go</code> files should not be listed in the <code>Makefile</code>.
+</p>
+
+<p>
+To run the test, run either <code>make test</code> or <code>gotest</code>
+(they are equivalent).
+To run only the tests in a single test file, for instance <code>one_test.go</code>,
+run <code>gotest one_test.go</code>.
+</p>
+
+<p>
+If your change affects performance, add a <code>Benchmark</code> function 
+(see the <a href="/cmd/gotest/">gotest command documentation</a>)
+and run it using <code>gotest -benchmarks=.</code>.
+</p>
+
+<p>
+Once your new code is tested and working,
+it's time to get it <a href="contribute.html">reviewed and submitted</a>.
+</p>
+

lib/godoc/godoc.html

@@ -91,6 +91,7 @@
     <li class="blank">&nbsp;</li>
     <li class="navhead">How To</li>
     <li><a href="/doc/install.html">Install Go</a></li>
+    <li><a href="/doc/code.html">Write code</a></li>
     <li><a href="/doc/contribute.html">Contribute code</a></li>
 
     <li class="blank">&nbsp;</li>