JSON export/import in generate-bindings.pl

Source/bindings/scripts/generate-bindings.pl

 #!/usr/bin/perl -w
 #
 # Copyright (C) 2005 Apple Computer, Inc.
 # Copyright (C) 2006 Anders Carlsson <andersca@mac.com>
 # 
 # This file is part of WebKit
 # 
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Library General Public
 # License as published by the Free Software Foundation; either
@@ skipping 20 matching lines @@
 use strict;
 
 use File::Path;
 use File::Basename;
 use Getopt::Long;
 use Text::ParseWords;
 use Cwd;
 
 use IDLParser;
 use CodeGeneratorV8;
+use IRToFromJSON qw(IRToJSON JSONToIR);
 
 my @idlDirectories;
 my $outputDirectory;
 my $outputHeadersDirectory;
 my $defines;
 my $filename;
 my $preprocessor;
 my $verbose;
 my $supplementalDependencyFile;
 my $additionalIdlFiles;
 my $idlAttributesFile;
 my $writeFileOnlyIfChanged;
+my $dumpJson = '';
+my $compileJson = '';
 
 GetOptions('include=s@' => \@idlDirectories,
            'outputDir=s' => \$outputDirectory,
            'outputHeadersDir=s' => \$outputHeadersDirectory,
            'defines=s' => \$defines,
            'filename=s' => \$filename,
            'preprocessor=s' => \$preprocessor,
            'verbose' => \$verbose,
            'supplementalDependencyFile=s' => \$supplementalDependencyFile,
            'additionalIdlFiles=s' => \$additionalIdlFiles,
            'idlAttributesFile=s' => \$idlAttributesFile,
-           'write-file-only-if-changed=s' => \$writeFileOnlyIfChanged);
+           'write-file-only-if-changed=s' => \$writeFileOnlyIfChanged,
+           'dump-json' => \$dumpJson,
+           'compile-json' => \$compileJson);

[haraken, 2013/06/12 03:20:21]

Are these options needed?

[Nils Barth (inactive), 2013/06/12 03:57:43]

Already removed in Patch Set 5.

We can make the build 2-step in 2 ways:
(A) Add options to generate-bindings.pl to either --dump-json, or
--compile-json.
(B) Split up generate-bindings.pl into two scripts, call them idl-to-json.pl and
compile-json.pl.

(A) is a shorter but messier patch and doesn't break the build,
(B) is cleaner but requires changing the build.
We can decide when we do step (2) Change the build.

 
 my $targetIdlFile = $ARGV[0];
 
 die('Must specify input file.') unless defined($targetIdlFile);
 die('Must specify output directory.') unless defined($outputDirectory);
 $defines = "" unless defined($defines);
 
 if (!$outputHeadersDirectory) {
     $outputHeadersDirectory = $outputDirectory;
 }
 $targetIdlFile = Cwd::realpath($targetIdlFile);
 if ($verbose) {
     print "$targetIdlFile\n";
 }
 my $targetInterfaceName = fileparse(basename($targetIdlFile), ".idl");
+my $jsonFilename = "${targetInterfaceName}.json";
 
 my $idlFound = 0;
 my @supplementedIdlFiles;
 if ($supplementalDependencyFile) {
     # The format of a supplemental dependency file:
     #
     # DOMWindow.idl P.idl Q.idl R.idl
     # Document.idl S.idl
     # Event.idl
     # ...
@@ skipping 19 matching lines @@
         $idlFound = grep { $_ and basename($_) eq basename($targetIdlFile) } @idlFiles;
     }
 
     if (!$idlFound) {
         # We generate empty .h and .cpp files just to tell build scripts that .h and .cpp files are created.
         generateEmptyHeaderAndCpp($targetInterfaceName, $outputHeadersDirectory, $outputDirectory);
         exit 0;
     }
 }
 
+my $targetDocument;

[dominicc (has gone to gerrit), 2013/06/11 22:56:30]

Can we instead wrap up the thing that sources the abstract syntax--either the
parser or the JSON reader--into a couple of functions. And then just do

if (...looks like we're doing JSON...) {
  ...read JSON...
} else {
  ...parse IDL...
}
do work (stuff I read I care not from whence it came);

It might be nice to deport them to separate files. Then when Python is done you
can just delete one of said files. It will be very clear what is going on.

[Nils Barth (inactive), 2013/06/12 02:56:12]

For now removed --dump-json/--compile-json from generate-bindings,
so these chunks no longer present.
Will bear comments in mind on next CL.

On 2013/06/11 22:56:30, dominicc wrote:
Yup, though we'd have to move the middle of generate-bindings.pl into a function
(notably the "foreach my $idlFile (@supplementedIdlFiles)" loop).
Yup.
Alternatively, just move to functions at the bottom of this file (current
IDLAttributes functions) and delete them.

+if ($compileJson) {
+    open FH, "< ${outputDirectory}/${jsonFilename}" or die "Cannot open $jsonFilename\n";
+    my @jsonLines = <FH>;
+    close FH;
+    my $jsonContents = join('', @jsonLines);
+    $targetDocument = JSONToIR($jsonContents);
+    goto COMPILE;

[haraken, 2013/06/12 03:20:21]

You can make this change in the next CL.

[Nils Barth (inactive), 2013/06/12 03:57:43]

Yes, that's what we're doing.

+}
+
 # Parse the target IDL file.
 my $targetParser = IDLParser->new(!$verbose);
-my $targetDocument = $targetParser->Parse($targetIdlFile, $defines, $preprocessor);
+$targetDocument = $targetParser->Parse($targetIdlFile, $defines, $preprocessor);
 
 if ($idlAttributesFile) {
     my $idlAttributes = loadIDLAttributes($idlAttributesFile);
     checkIDLAttributes($idlAttributes, $targetDocument, basename($targetIdlFile));
 }
 
 foreach my $idlFile (@supplementedIdlFiles) {
     next if $idlFile eq $targetIdlFile;
 
     my $interfaceName = fileparse(basename($idlFile), ".idl");
@@ skipping 45 matching lines @@
                     $constant->extendedAttributes->{$extendedAttributeName} = $interface->extendedAttributes->{$extendedAttributeName};
                 }
                 push(@{$targetDataNode->constants}, $constant);
             }
         } else {
             die "$idlFile is not a supplemental dependency of $targetIdlFile. There maybe a bug in the the supplemental dependency generator (preprocess_idls.py).\n";
         }
     }
 }
 
+# If dumping JSON, generate JSON output and exit

[dominicc (has gone to gerrit), 2013/06/11 22:56:30]

I will say this again, but I think you should do the actual file reading writing
part in a separate change when they will be actually used by a new step in gyp.

[Nils Barth (inactive), 2013/06/12 02:56:12]

Removed.

[haraken, 2013/06/12 03:20:21]

Yes, this should be in the next CL.

[Nils Barth (inactive), 2013/06/12 03:57:43]

ACK.

+if ($dumpJson) {
+    my $jsonText = IRToJSON($targetDocument);
+    open FH, "> ${outputDirectory}/${jsonFilename}" or die "Cannot open $jsonFilename\n";
+    print FH $jsonText;
+    close FH;
+    exit 0;
+}
+
+# Roundtrip to/from JSON to verify code

[haraken, 2013/06/12 03:20:21]

Instead you can say:

# FIXME: This code will be soon removed once IDLParser.pm and CodeGeneratorV8.pm
are connected via JSON files. See crbug/xxxx.

[Nils Barth (inactive), 2013/06/12 03:57:43]

Done.

+$targetDocument = JSONToIR(IRToJSON($targetDocument));
+
 # Generate desired output for the target IDL file.
+COMPILE:
 my @dependentIdlFiles = ($targetDocument->fileName(), @supplementedIdlFiles);
 my $codeGenerator = CodeGeneratorV8->new($targetDocument, \@idlDirectories, $preprocessor, $defines, $verbose, \@dependentIdlFiles, $writeFileOnlyIfChanged);
 my $interfaces = $targetDocument->interfaces;
 foreach my $interface (@$interfaces) {
     print "Generating bindings code for IDL interface \"" . $interface->name . "\"...\n" if $verbose;
     $codeGenerator->GenerateInterface($interface);
     $codeGenerator->WriteData($interface, $outputDirectory, $outputHeadersDirectory);
 }
 
 sub generateEmptyHeaderAndCpp
@@ skipping 93 matching lines @@
                 last OUTER;
             }
         }
     }
     if ($error) {
         die "IDL ATTRIBUTE CHECKER ERROR: $error
 If you want to add a new IDL attribute, you need to add it to bindings/scripts/IDLAttributes.txt and add explanations to the Blink IDL document (http://chromium.org/blink/webidl).
 ";
     }
 }