Add a summary() function for configuration summarization

Based on patch from Dylan Baker.

Fixes mesonbuild#757

data/syntax-highlighting/vim/syntax/meson.vim

@@ -117,6 +117,7 @@ syn keyword mesonBuiltin
   \ subdir
   \ subdir_done
   \ subproject
+  \ summary
   \ target_machine
   \ test
   \ vcs_tag

docs/markdown/Reference-manual.md

@@ -1206,6 +1206,62 @@ This function prints its argument to stdout prefixed with WARNING:.
 
 *Added 0.44.0*
 
+### summary()
+
+``` meson
+    void summary(section, value)
+```
+
+This function is used to summarize build configuration at the end of the build
+process. This function provides a way for projects (and subprojects) to report
+this information in a clear way.
+
+The first argument is a section name, the second argument is either a string
+or a dictionary. `summary()` can be called multiple times with a different
+section name at each invocation. All sections will be collected and printed at
+the end of the configuration in the same order as they have been called.
+
+- `summary('section1', 'foo')` will print `Section1 = foo`,
+- `summary('section2', {'foo': 'bar'})` will print:
+  ```
+  Section1
+    foo = bar
+  ```
+
+Dictionaries values can only be lists, dictionaries, integers, booleans or strings.
+Lists and dictionaries values will be pretty printed as `['a', 'b', ...]` and
+`{'a': b, ...}` respectively.
+
+Example:
+```meson
+sec1 = {'driver' : 'foobar', 'OS' : 'Linux', 'API' : '1.7'}
+sec2 = {'driver' : 'dive comp', 'OS' : 'Minix', 'API' : '1.1.2'}
+sec3 = {'with' : {'mesa' : true, 'gbm' : false}}
+
+summary('Backend', 'OpenGL')
+summary('Server', sec1)
+summary('Client', sec2)
+summary('Misc', sec3)
+```
+
+Output:
+```
+Main Project:
+  Backend = OpenGL
+  Server
+    driver = 'foobar'
+    OS = 'Linux'
+    API = '1.7'
+  Client
+    driver = 'dive comp'
+    OS = 'Minix'
+    API = '1.1.2'
+  Misc
+    with = {'mesa' : True, 'gbm' : False}
+```
+
+*Added 0.53.0*
+
 ### project()
 
 ``` meson

docs/markdown/snippets/summary.md

@@ -0,0 +1,32 @@
+## Add a new summary() function
+
+A new function [`summary()`](Reference-manual.md#summary) has been added to
+summarize build configuration at the end of the build process.
+
+Example:
+```meson
+sec1 = {'driver' : 'foobar', 'OS' : 'Linux', 'API' : '1.7'}
+sec2 = {'driver' : 'dive comp', 'OS' : 'Minix', 'API' : '1.1.2'}
+sec3 = {'with' : {'mesa' : true, 'gbm' : false}}
+
+summary('Backend', 'OpenGL')
+summary('Server', sec1)
+summary('Client', sec2)
+summary('Misc', sec3)
+```
+
+Output:
+```
+Main Project:
+  Backend = OpenGL
+  Server
+    driver = 'foobar'
+    OS = 'Linux'
+    API = '1.7'
+  Client
+    driver = 'dive comp'
+    OS = 'Minix'
+    API = '1.1.2'
+  Misc
+    with = {'mesa' : True, 'gbm' : False}
+```

mesonbuild/ast/interpreter.py

@@ -119,6 +119,7 @@ def __init__(self, source_root: str, subdir: str, visitors: Optional[List[AstVis
                            'find_library': self.func_do_nothing,
                            'subdir_done': self.func_do_nothing,
                            'alias_target': self.func_do_nothing,
+                           'summary': self.func_do_nothing,
                            })
 
     def func_do_nothing(self, node, args, kwargs):

mesonbuild/interpreter.py

@@ -38,7 +38,7 @@
 import os, shutil, uuid
 import re, shlex
 import subprocess
-from collections import namedtuple
+import collections
 from itertools import chain
 import functools
 from typing import Sequence, List, Union, Optional, Dict, Any
@@ -50,15 +50,15 @@
                            'sources'},
 }
 
-def stringifyUserArguments(args):
+def stringifyUserArguments(args, quote_string=True):
     if isinstance(args, list):
         return '[%s]' % ', '.join([stringifyUserArguments(x) for x in args])
     elif isinstance(args, dict):
         return '{%s}' % ', '.join(['%s : %s' % (stringifyUserArguments(k), stringifyUserArguments(v)) for k, v in args.items()])
     elif isinstance(args, int):
         return str(args)
     elif isinstance(args, str):
-        return "'%s'" % args
+        return '{!r}'.format(args) if quote_string else args
     raise InvalidArguments('Function accepts only strings, integers, lists and lists thereof.')
 
 
@@ -1691,7 +1691,7 @@ def get_argument_syntax_method(self, args, kwargs):
         return self.compiler.get_argument_syntax()
 
 
-ModuleState = namedtuple('ModuleState', [
+ModuleState = collections.namedtuple('ModuleState', [
     'source_root', 'build_to_src', 'subproject', 'subdir', 'current_lineno', 'environment',
     'project_name', 'project_version', 'backend', 'targets',
     'data', 'headers', 'man', 'global_args', 'project_args', 'build_machine',
@@ -1751,6 +1751,50 @@ def method_call(self, method_name, args, kwargs):
                 raise InterpreterException('Extension module altered internal state illegally.')
             return self.interpreter.module_method_callback(value)
 
+
+class Summary:
+    def __init__(self):
+        self.sections = collections.defaultdict(dict)
+        self.max_key_width = 0
+
+    def add_section(self, section, values):
+        for k, v in values.items():
+            if k in self.sections[section]:
+                raise InterpreterException('Summary section {!r} already have key {!r}'.format(section, k))
+            if isinstance(v, list):
+                check_values = v
+            elif isinstance(v, dict):
+                check_values = v.values()
+            else:
+                check_values = [v]
+            for i in check_values:
+                if not isinstance(i, (str, int)):
+                    raise InterpreterException()
+            self.sections[section][k] = v
+        self.max_key_width = max(self.max_key_width, max([len(i) for i in values.keys()]))
+
+    def dump(self):
+        for section, values in self.sections.items():
+            mlog.log('')  # newline
+            mlog.log(' ', mlog.bold(section))
+            for k, v in values.items():
+                indent = self.max_key_width - len(k) + 3
+                if isinstance(v, list):
+                    mlog.log(' ' * indent, k + ':', v[0])
+                    indent += len(k) + 2
+                    for i in v[1:]:
+                        mlog.log(' ' * indent, i)
+                elif isinstance(v, dict):
+                    v_items = list(v.items())
+                    mlog.log(' ' * indent, k + ':', v_items[0][0], '=', v_items[0][1])
+                    indent += len(k) + 2
+                    for i in v_items[1:]:
+                        mlog.log(' ' * indent, i[0], '=', i[1])
+                else:
+                    mlog.log(' ' * indent, k + ':', v)
+        mlog.log('')  # newline
+
+
 class MesonMain(InterpreterObject):
     def __init__(self, build, interpreter):
         InterpreterObject.__init__(self)
@@ -2078,6 +2122,7 @@ def __init__(self, build, backend=None, subproject='', subdir='', subproject_dir
         self.coredata = self.environment.get_coredata()
         self.backend = backend
         self.subproject = subproject
+        self.summary = collections.defaultdict(Summary)
         if modules is None:
             self.modules = {}
         else:
@@ -2188,6 +2233,7 @@ def build_func_dict(self):
                            'subdir': self.func_subdir,
                            'subdir_done': self.func_subdir_done,
                            'subproject': self.func_subproject,
+                           'summary': self.func_summary,
                            'shared_library': self.func_shared_lib,
                            'shared_module': self.func_shared_module,
                            'static_library': self.func_static_lib,
@@ -2594,6 +2640,7 @@ def _do_subproject_meson(self, dirname, subdir, default_options, kwargs, ast=Non
             self.build_def_files = list(set(self.build_def_files + subi.build_def_files))
         self.build.merge(subi.build)
         self.build.subprojects[dirname] = subi.project_version
+        self.summary.update(subi.summary)
         return self.subprojects[dirname]
 
     def _do_subproject_cmake(self, dirname, subdir, subdir_abs, default_options, kwargs):
@@ -2802,38 +2849,52 @@ def func_add_languages(self, node, args, kwargs):
             return False
         return self.add_languages(args, required)
 
-    def get_message_string_arg(self, node):
-        # reduce arguments again to avoid flattening posargs
-        (posargs, _) = self.reduce_arguments(node.args)
+    def get_message_string_arg(self, posargs):
         if len(posargs) != 1:
             raise InvalidArguments('Expected 1 argument, got %d' % len(posargs))
+        return stringifyUserArguments(posargs[0], quote_string=False)
 
-        arg = posargs[0]
-        if isinstance(arg, list):
-            argstr = stringifyUserArguments(arg)
-        elif isinstance(arg, dict):
-            argstr = stringifyUserArguments(arg)
-        elif isinstance(arg, str):
-            argstr = arg
-        elif isinstance(arg, int):
-            argstr = str(arg)
-        else:
-            raise InvalidArguments('Function accepts only strings, integers, lists and lists thereof.')
-
-        return argstr
-
+    @noArgsFlattening
     @noKwargs
     def func_message(self, node, args, kwargs):
-        argstr = self.get_message_string_arg(node)
+        argstr = self.get_message_string_arg(args)
         self.message_impl(argstr)
 
     def message_impl(self, argstr):
         mlog.log(mlog.bold('Message:'), argstr)
 
+    @noArgsFlattening
+    @noKwargs
+    @FeatureNew('summary', '0.53.0')
+    def func_summary(self, node, args, kwargs):
+        if len(args) != 2:
+            raise InterpreterException('Summary accepts exactly two arguments.')
+        section, values = args
+        if not isinstance(section, str):
+            raise InterpreterException('Argument 1 must be a string.')
+        if not isinstance(values, dict):
+            raise InterpreterException('Argument 2 must be a dictionary.')
+        self.summary[self.subproject].add_section(section, values)
+
+    def _print_summary(self):
+        mlog.log('')  # newline
+        for project, summary in sorted(self.summary.items()):
+            if project == '':
+                continue
+            subi = self.subprojects[project].held_object
+            project_name = self.build.projects[project]
+            project_version = subi.project_version
+            mlog.log(project_name, mlog.normal_cyan(project_version))
+            summary.dump()
+
+        if '' in self.summary:
+            mlog.log(self.build.project_name, mlog.normal_cyan(self.project_version))
+            self.summary[''].dump()
+
     @FeatureNew('warning', '0.44.0')
     @noKwargs
     def func_warning(self, node, args, kwargs):
-        argstr = self.get_message_string_arg(node)
+        argstr = self.get_message_string_arg(args)
         mlog.warning(argstr, location=node)
 
     @noKwargs
@@ -4070,6 +4131,8 @@ def run(self):
         FeatureDeprecated.report(self.subproject)
         if not self.is_subproject():
             self.print_extra_warnings()
+        if self.subproject == '':
+            self._print_summary()
 
     def print_extra_warnings(self):
         # TODO cross compilation

run_unittests.py

@@ -4128,6 +4128,36 @@ def test_configure(self):
         self.init(testdir)
         self._run(self.mconf_command + [self.builddir])
 
+    def test_summary(self):
+        testdir = os.path.join(self.unit_test_dir, '74 summary')
+        out = self.init(testdir)
+        self.assertRegex(out, textwrap.dedent(r'''
+            Some Subproject 2.0
+
+              Features
+                foo: bar
+
+            My Project 1.0
+
+              Directories
+                         prefix: /usr
+                         bindir: bin
+                         libdir: lib
+                        datadir: share
+
+              Configuration
+                   Some boolean: False
+                Another boolean: True
+                    Some string: Hello World
+                         A list: string
+                                 1
+                                 True
+                         A dict: key1 = string
+                                 key2 = 1
+                                 key3 = True
+            '''))
+
+
 class FailureTests(BasePlatformTests):
     '''
     Tests that test failure conditions. Build files here should be dynamically

test cases/unit/74 summary/meson.build

@@ -0,0 +1,23 @@
+project('My Project', version : '1.0')
+
+sec1 = {'driver' : 'foobar'}
+sec2 = {'driver' : 'dive comp', 'API' : '1.1.2'}
+sec3 = {'with' : {'mesa' : true, 'gbm' : false}}
+
+
+subproject('sub')
+subproject('sub2', required : false)
+
+summary('Directories', {'prefix': get_option('prefix'),
+                        'bindir': get_option('bindir'),
+                        'libdir': get_option('libdir'),
+                        'datadir': get_option('datadir'),
+                        })
+summary('Configuration', {'Some boolean': false,
+                          'Another boolean': true,
+                          'Some string': 'Hello World',
+                          'A list': ['string', 1, true],
+                          'A dict': {'key1': 'string',
+                                     'key2': 1,
+                                     'key3': true}
+                          })

test cases/unit/74 summary/subprojects/sub/meson.build

@@ -0,0 +1,3 @@
+project('Some Subproject', version : '2.0')
+
+summary('Features', {'foo': 'bar'})

test cases/unit/74 summary/subprojects/sub2/meson.build

@@ -0,0 +1,5 @@
+project('sub2')
+
+error('This subproject failed')
+
+summary('Section', 'Should not be seen')