- added an explicit Gs() Builder to the gs.py Tool

- updated documentation accordingly and added a (very) simple test

7 files changed, 95 insertions, 26 deletions

diff --git a/doc/generated/builders.gen b/doc/generated/builders.gen
index 3fdafb6..5cd92f2 100644
--- a/doc/generated/builders.gen
+++ b/doc/generated/builders.gen
@@ -397,6 +397,27 @@ env.DVI(target = 'ccc.dvi', source = 'ccc.latex')
 </example_commands>
 </listitem>
   </varlistentry>
+  <varlistentry id="b-Gs">
+    <term>
+      <function>Gs()</function>
+    </term>
+    <term>
+      <function>env.Gs()</function>
+    </term>
+    <listitem>
+<para xmlns="http://www.scons.org/dbxsd/v1.0">
+A Builder for explicitly calling the <literal>gs</literal> executable.
+Depending on the underlying OS, the different names <literal>gs</literal>,
+<literal>gsos2</literal> and <literal>gswin32c</literal>
+are tried.
+</para>
+<example_commands xmlns="http://www.scons.org/dbxsd/v1.0">env = Environment(tools=['gs'])
+env.Gs('cover.jpg','scons-scons.pdf',
+       GSFLAGS='-dNOPAUSE -dBATCH -sDEVICE=jpeg -dFirstPage=1 -dLastPage=1 -q') 
+       )
+</example_commands>
+</listitem>
+  </varlistentry>
   <varlistentry id="b-Install">
     <term>
       <function>Install()</function>
diff --git a/doc/generated/builders.mod b/doc/generated/builders.mod
index 59900cc..b8c7d80 100644
--- a/doc/generated/builders.mod
+++ b/doc/generated/builders.mod
@@ -21,6 +21,7 @@ THIS IS AN AUTOMATICALLY-GENERATED FILE.  DO NOT EDIT.
 <!ENTITY b-DocbookXInclude "<function xmlns='http://www.scons.org/dbxsd/v1.0'>DocbookXInclude</function>">
 <!ENTITY b-DocbookXslt "<function xmlns='http://www.scons.org/dbxsd/v1.0'>DocbookXslt</function>">
 <!ENTITY b-DVI "<function xmlns='http://www.scons.org/dbxsd/v1.0'>DVI</function>">
+<!ENTITY b-Gs "<function xmlns='http://www.scons.org/dbxsd/v1.0'>Gs</function>">
 <!ENTITY b-Install "<function xmlns='http://www.scons.org/dbxsd/v1.0'>Install</function>">
 <!ENTITY b-InstallAs "<function xmlns='http://www.scons.org/dbxsd/v1.0'>InstallAs</function>">
 <!ENTITY b-InstallVersionedLib "<function xmlns='http://www.scons.org/dbxsd/v1.0'>InstallVersionedLib</function>">
@@ -74,6 +75,7 @@ THIS IS AN AUTOMATICALLY-GENERATED FILE.  DO NOT EDIT.
 <!ENTITY b-env-DocbookXInclude "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.DocbookXInclude</function>">
 <!ENTITY b-env-DocbookXslt "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.DocbookXslt</function>">
 <!ENTITY b-env-DVI "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.DVI</function>">
+<!ENTITY b-env-Gs "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.Gs</function>">
 <!ENTITY b-env-Install "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.Install</function>">
 <!ENTITY b-env-InstallAs "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.InstallAs</function>">
 <!ENTITY b-env-InstallVersionedLib "<function xmlns='http://www.scons.org/dbxsd/v1.0'>env.InstallVersionedLib</function>">
@@ -137,6 +139,7 @@ THIS IS AN AUTOMATICALLY-GENERATED FILE.  DO NOT EDIT.
 <!ENTITY b-link-DocbookXInclude "<link linkend='b-DocbookXInclude' xmlns='http://www.scons.org/dbxsd/v1.0'><function>DocbookXInclude</function></link>">
 <!ENTITY b-link-DocbookXslt "<link linkend='b-DocbookXslt' xmlns='http://www.scons.org/dbxsd/v1.0'><function>DocbookXslt</function></link>">
 <!ENTITY b-link-DVI "<link linkend='b-DVI' xmlns='http://www.scons.org/dbxsd/v1.0'><function>DVI</function></link>">
+<!ENTITY b-link-Gs "<link linkend='b-Gs' xmlns='http://www.scons.org/dbxsd/v1.0'><function>Gs</function></link>">
 <!ENTITY b-link-Install "<link linkend='b-Install' xmlns='http://www.scons.org/dbxsd/v1.0'><function>Install</function></link>">
 <!ENTITY b-link-InstallAs "<link linkend='b-InstallAs' xmlns='http://www.scons.org/dbxsd/v1.0'><function>InstallAs</function></link>">
 <!ENTITY b-link-InstallVersionedLib "<link linkend='b-InstallVersionedLib' xmlns='http://www.scons.org/dbxsd/v1.0'><function>InstallVersionedLib</function></link>">
@@ -190,6 +193,7 @@ THIS IS AN AUTOMATICALLY-GENERATED FILE.  DO NOT EDIT.
 <!ENTITY b-link-env-DocbookXInclude "<link linkend='b-DocbookXInclude' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.DocbookXInclude</function></link>">
 <!ENTITY b-link-env-DocbookXslt "<link linkend='b-DocbookXslt' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.DocbookXslt</function></link>">
 <!ENTITY b-link-env-DVI "<link linkend='b-DVI' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.DVI</function></link>">
+<!ENTITY b-link-env-Gs "<link linkend='b-Gs' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.Gs</function></link>">
 <!ENTITY b-link-env-Install "<link linkend='b-Install' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.Install</function></link>">
 <!ENTITY b-link-env-InstallAs "<link linkend='b-InstallAs' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.InstallAs</function></link>">
 <!ENTITY b-link-env-InstallVersionedLib "<link linkend='b-InstallVersionedLib' xmlns='http://www.scons.org/dbxsd/v1.0'><function>env.InstallVersionedLib</function></link>">
diff --git a/doc/generated/tools.gen b/doc/generated/tools.gen
index 57bb0a2..7d75638 100644
--- a/doc/generated/tools.gen
+++ b/doc/generated/tools.gen
@@ -444,7 +444,12 @@ Set construction variables for GNU linker/loader.
     <term>gs</term>
     <listitem>
 <para xmlns="http://www.scons.org/dbxsd/v1.0">
-Set construction variables for Ghostscript.
+This Tool sets the required construction variables for working with
+the Ghostscript command. It also registers an appropriate Action
+with the PDF Builder (<link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="b-PDF"><function>PDF</function></link>), such that the conversion from
+PS/EPS to PDF happens automatically for the TeX/LaTeX toolchain.
+Finally, it adds an explicit Ghostscript Builder (<link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="b-Gs"><function>Gs</function></link>) to the
+environment.
 </para>
 <para>Sets:  &cv-link-GS;, &cv-link-GSCOM;, &cv-link-GSFLAGS;.</para><para>Uses:  &cv-link-GSCOMSTR;.</para></listitem>
   </varlistentry>
diff --git a/doc/generated/variables.gen b/doc/generated/variables.gen
index 784cd28..ee5a0dd 100644
--- a/doc/generated/variables.gen
+++ b/doc/generated/variables.gen
@@ -2324,7 +2324,7 @@ described above.)
     <term>GS</term>
     <listitem>
 <para xmlns="http://www.scons.org/dbxsd/v1.0">
-The Ghostscript program used to convert PostScript to PDF files.
+The Ghostscript program used, e.g. to convert PostScript to PDF files.
 </para>
 </listitem>
   </varlistentry>
@@ -2332,7 +2332,8 @@ The Ghostscript program used to convert PostScript to PDF files.
     <term>GSCOM</term>
     <listitem>
 <para xmlns="http://www.scons.org/dbxsd/v1.0">
-The Ghostscript command line used to convert PostScript to PDF files.
+The full Ghostscript command line used for the conversion process. Its default
+value is <quote><literal>$GS $GSFLAGS -sOutputFile=$TARGET $SOURCES</literal></quote>.
 </para>
 </listitem>
   </varlistentry>
@@ -2341,9 +2342,8 @@ The Ghostscript command line used to convert PostScript to PDF files.
     <listitem>
 <para xmlns="http://www.scons.org/dbxsd/v1.0">
 The string displayed when
-Ghostscript is used to convert
-a PostScript file to a PDF file.
-If this is not set, then <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="cv-GSCOM"><envar>$GSCOM</envar></link> (the command line) is displayed.
+Ghostscript is called for the conversion process.
+If this is not set (the default), then <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="cv-GSCOM"><envar>$GSCOM</envar></link> (the command line) is displayed.
 </para>
 </listitem>
   </varlistentry>
@@ -2351,8 +2351,9 @@ If this is not set, then <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="
     <term>GSFLAGS</term>
     <listitem>
 <para xmlns="http://www.scons.org/dbxsd/v1.0">
-General options passed to the Ghostscript program
-when converting PostScript to PDF files.
+General options passed to the Ghostscript program,
+when converting PostScript to PDF files for example. Its default value
+is <quote><literal>-dNOPAUSE -dBATCH -sDEVICE=pdfwrite</literal></quote>
 </para>
 </listitem>
   </varlistentry>
@@ -3548,6 +3549,9 @@ See <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="t-msginit"><literal>m
 Internal ``macro''. Computes locale (language) name based on target filename
 (default: <literal>'${TARGET.filebase}' </literal>).
 </para>
+<para xmlns="http://www.scons.org/dbxsd/v1.0">
+See <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="t-msginit"><literal>msginit</literal></link> tool and <link xmlns="http://www.scons.org/dbxsd/v1.0" linkend="b-POInit"><function>POInit</function></link> builder.
+</para>
 </listitem>
   </varlistentry>
   <varlistentry id="cv-MSGMERGE">
diff --git a/src/engine/SCons/Tool/gs.py b/src/engine/SCons/Tool/gs.py
index ada169a..a8fddde 100644
--- a/src/engine/SCons/Tool/gs.py
+++ b/src/engine/SCons/Tool/gs.py
@@ -34,6 +34,7 @@ selection method.
 __revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 import SCons.Action
+import SCons.Builder
 import SCons.Platform
 import SCons.Util
 
@@ -52,17 +53,27 @@ GhostscriptAction = None
 def generate(env):
     """Add Builders and construction variables for Ghostscript to an
     Environment."""
-
     global GhostscriptAction
-    if GhostscriptAction is None:
-        GhostscriptAction = SCons.Action.Action('$GSCOM', '$GSCOMSTR')
-
-    import pdf
-    pdf.generate(env)
-
-    bld = env['BUILDERS']['PDF']
-    bld.add_action('.ps', GhostscriptAction)
-
+    # The following try-except block enables us to use the Tool
+    # in standalone mode (without the accompanying pdf.py),
+    # whenever we need an explicit call of gs via the Gs()
+    # Builder ...
+    try:
+        if GhostscriptAction is None:
+            GhostscriptAction = SCons.Action.Action('$GSCOM', '$GSCOMSTR')
+    
+        import pdf
+        pdf.generate(env)
+    
+        bld = env['BUILDERS']['PDF']
+        bld.add_action('.ps', GhostscriptAction)
+    except ImportError, e:
+        pass
+
+    gsbuilder = SCons.Builder.Builder(action = SCons.Action.Action('$GSCOM', '$GSCOMSTR'),
+                                      env = env)
+    env['BUILDERS']['Gs'] = gsbuilder
+    
     env['GS']      = gs
     env['GSFLAGS'] = SCons.Util.CLVar('-dNOPAUSE -dBATCH -sDEVICE=pdfwrite')
     env['GSCOM']   = '$GS $GSFLAGS -sOutputFile=$TARGET $SOURCES'
diff --git a/src/engine/SCons/Tool/gs.xml b/src/engine/SCons/Tool/gs.xml
index c34f004..3fe5165 100644
--- a/src/engine/SCons/Tool/gs.xml
+++ b/src/engine/SCons/Tool/gs.xml
@@ -26,7 +26,12 @@ See its __doc__ string for a discussion of the format.
 <tool name="gs">
 <summary>
 <para>
-Set construction variables for Ghostscript.
+This Tool sets the required construction variables for working with
+the Ghostscript command. It also registers an appropriate Action
+with the PDF Builder (&b-link-PDF;), such that the conversion from
+PS/EPS to PDF happens automatically for the TeX/LaTeX toolchain.
+Finally, it adds an explicit Ghostscript Builder (&b-link-Gs;) to the
+environment.
 </para>
 </summary>
 <sets>
@@ -42,7 +47,7 @@ Set construction variables for Ghostscript.
 <cvar name="GS">
 <summary>
 <para>
-The Ghostscript program used to convert PostScript to PDF files.
+The Ghostscript program used, e.g. to convert PostScript to PDF files.
 </para>
 </summary>
 </cvar>
@@ -50,7 +55,8 @@ The Ghostscript program used to convert PostScript to PDF files.
 <cvar name="GSCOM">
 <summary>
 <para>
-The Ghostscript command line used to convert PostScript to PDF files.
+The full Ghostscript command line used for the conversion process. Its default
+value is <quote><literal>$GS $GSFLAGS -sOutputFile=$TARGET $SOURCES</literal></quote>.
 </para>
 </summary>
 </cvar>
@@ -59,9 +65,8 @@ The Ghostscript command line used to convert PostScript to PDF files.
 <summary>
 <para>
 The string displayed when
-Ghostscript is used to convert
-a PostScript file to a PDF file.
-If this is not set, then &cv-link-GSCOM; (the command line) is displayed.
+Ghostscript is called for the conversion process.
+If this is not set (the default), then &cv-link-GSCOM; (the command line) is displayed.
 </para>
 </summary>
 </cvar>
@@ -69,10 +74,27 @@ If this is not set, then &cv-link-GSCOM; (the command line) is displayed.
 <cvar name="GSFLAGS">
 <summary>
 <para>
-General options passed to the Ghostscript program
-when converting PostScript to PDF files.
+General options passed to the Ghostscript program,
+when converting PostScript to PDF files for example. Its default value
+is <quote><literal>-dNOPAUSE -dBATCH -sDEVICE=pdfwrite</literal></quote>
 </para>
 </summary>
 </cvar>
 
+<builder name="Gs">
+<summary>
+<para>
+A Builder for explicitly calling the <literal>gs</literal> executable.
+Depending on the underlying OS, the different names <literal>gs</literal>,
+<literal>gsos2</literal> and <literal>gswin32c</literal>
+are tried.
+</para>
+<example_commands>env = Environment(tools=['gs'])
+env.Gs('cover.jpg','scons-scons.pdf',
+       GSFLAGS='-dNOPAUSE -dBATCH -sDEVICE=jpeg -dFirstPage=1 -dLastPage=1 -q') 
+       )
+</example_commands>
+</summary>
+</builder>
+
 </sconsdoc>
\ No newline at end of file
diff --git a/test/Ghostscript/GS.py b/test/Ghostscript/GS.py
index 2cae8b8..daeea09 100644
--- a/test/Ghostscript/GS.py
+++ b/test/Ghostscript/GS.py
@@ -51,6 +51,7 @@ env = Environment(GS = r'%(_python_)s mygs.py',
                   GSCOM = r'$GS $TARGET $SOURCE',
                   tools=['gs'])
 env.PDF(target = 'test1.pdf', source = 'test1.ps')
+env.Gs(target = 'test2.pdf', source = 'test1.ps')
 """ % locals())
 
 test.write('test1.ps', r"""This is a .ps test.
@@ -60,6 +61,7 @@ test.write('test1.ps', r"""This is a .ps test.
 test.run(arguments = '.', stderr = None)
 
 test.fail_test(test.read('test1.pdf') != "This is a .ps test.\n")
+test.fail_test(test.read('test2.pdf') != "This is a .ps test.\n")