Re-add some accidentally deleted docs.

These were accidentally deleted in
https://github.com/bazelbuild/bazel/commit/7dec00574aa91327693f6ba7e90bff5bc834253e.

RELNOTES: None
PiperOrigin-RevId: 158404948

1 files changed, 58 insertions, 0 deletions

diff --git a/site/docs/query.html b/site/docs/query.html
index 7c30dfbfab..968428460d 100644
--- a/site/docs/query.html
+++ b/site/docs/query.html
@@ -1235,6 +1235,64 @@ maxrank
   <code>@repo//foo/bar</code> while packages in the main repository are
   formatted as <code>foo/bar</code>.
 </p>
+<p>
+  In conjunction with the <code>deps(...)</code> query, this output
+  option can be used to find the set of packages that must be checked
+  out in order to build a given set of targets.
+</p>
+
+<h3 id="output-graph">Display a graph of the result</h3>
+<pre>--output graph</pre>
+<p>
+  This option causes the query result to be printed as a directed
+  graph in the popular AT&amp;T GraphViz format.  Typically the
+  result is saved to a file, such as <code>.png</code> or <code>.svg</code>.
+  (If the <code>dot</code> program is not installed on your workstation, you
+  can install it using the command <code>sudo apt-get install graphviz</code>.)
+  See the example section below for a sample invocation.
+</p>
+
+<p>
+  This output format is particularly useful for <code>allpath</code>,
+  <code>deps</code>, or <code>rdeps</code> queries, where the result
+  includes a <em>set of paths</em> that cannot be easily visualized when
+  rendered in a linear form, such as with <code>--output label</code>.
+</p>
+
+<p>
+  By default, the graph is rendered in a <em>factored</em> form.  That is,
+  topologically-equivalent nodes are merged together into a single
+  node with multiple labels.  This makes the graph more compact
+  and readable, because typical result graphs contain highly
+  repetitive patterns.  For example, a <code>java_library</code> rule
+  may depend on hundreds of Java source files all generated by the
+  same <code>genrule</code>; in the factored graph, all these files
+  are represented by a single node.  This behavior may be disabled
+  with the <code>--nograph:factored</code> option.
+</p>
+
+<h4><code>--graph:node_limit <var>n</var></code></h4>
+<p>
+  The option specifies the maximum length of the label string for a
+  graph node in the output.  Longer labels will be truncated; -1
+  disables truncation.  Due to the factored form in which graphs are
+  usually printed, the node labels may be very long.  GraphViz cannot
+  handle labels exceeding 1024 characters, which is the default value
+  of this option.  This option has no effect unless
+  <code>--output=graph</code> is being used.
+</p>
+
+<h4><code>--[no]graph:factored</code></h4>
+<p>
+  By default, graphs are displayed in factored form, as explained
+  <a href='#output-graph'>above</a>.
+  When <code>--nograph:factored</code> is specified, graphs are
+  printed without factoring.  This makes visualization using GraphViz
+  impractical, but the simpler format may ease processing by other
+  tools (e.g. grep).  This option has no effect
+  unless <code>--output=graph</code> is being used.
+</p>
+
 <h3 id="output-xml">XML</h3>
 <pre>--output xml</pre>
 <p>