Fix consistency in variables kwarg

Share common code to extract the `variables` kwarg in
declare_dependency() and pkg.generate().

11 files changed, 58 insertions, 31 deletions

diff --git a/docs/markdown/Pkgconfig-module.md b/docs/markdown/Pkgconfig-module.md
index 7b68e2408..e9aa4a226 100644
--- a/docs/markdown/Pkgconfig-module.md
+++ b/docs/markdown/Pkgconfig-module.md
@@ -49,7 +49,8 @@ keyword arguments.
   generated file. The strings must be in the form `name=value` and may
   reference other pkgconfig variables,
   e.g. `datadir=${prefix}/share`. The names `prefix`, `libdir` and
-  `includedir` are reserved and may not be used.
+  `includedir` are reserved and may not be used. *Since 0.56.0* it can also be a
+  dictionary.
 - `version` a string describing the version of this library, used to set the
   `Version:` field. (*since 0.46.0*) Defaults to the project version if unspecified.
 - `d_module_versions` a list of module version flags used when compiling
diff --git a/docs/markdown/Reference-manual.md b/docs/markdown/Reference-manual.md
index 38ae5582b..13111d1cc 100644
--- a/docs/markdown/Reference-manual.md
+++ b/docs/markdown/Reference-manual.md
@@ -427,7 +427,7 @@ keyword arguments:
 - `version`: the version of this dependency, such as `1.2.3`
 - `variables` *(since 0.54.0)*: a dictionary of arbitrary strings, this is meant to be used
   in subprojects where special variables would be provided via cmake or
-  pkg-config.
+  pkg-config. *since 0.56.0* it can also be a list of `'key=value'` strings.
 
 ### dependency()
 
diff --git a/docs/markdown/snippets/pkg_idep_variables.md b/docs/markdown/snippets/pkg_idep_variables.md
new file mode 100644
index 000000000..4e69b18e3
--- /dev/null
+++ b/docs/markdown/snippets/pkg_idep_variables.md
@@ -0,0 +1,12 @@
+## Consistency between `declare_dependency()` and `pkgconfig.generate()` variables
+
+The `variables` keyword argument in `declare_dependency()` used to only support
+dictionary and `pkgconfig.generate()` only list of strings. They now both support
+dictionary and list of strings in the format `'name=value'`. This makes easier
+to share a common set of variables for both:
+
+```meson
+vars = {'foo': 'bar'}
+dep = declare_dependency(..., variables: vars)
+pkg.generate(..., variables: vars)
+```
diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index ad6f04eb7..cd201d097 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -2680,6 +2680,32 @@ class Interpreter(InterpreterBase):
     def func_files(self, node, args, kwargs):
         return [mesonlib.File.from_source_file(self.environment.source_dir, self.subdir, fname) for fname in args]
 
+    # Used by declare_dependency() and pkgconfig.generate()
+    def extract_variables(self, kwargs, argname='variables', list_new=False, dict_new=False):
+        variables = kwargs.get(argname, {})
+        if isinstance(variables, dict):
+            if dict_new and variables:
+                FeatureNew.single_use('variables as dictionary', '0.56.0', self.subproject)
+        else:
+            varlist = mesonlib.stringlistify(variables)
+            if list_new:
+                FeatureNew.single_use('variables as list of strings', '0.56.0', self.subproject)
+            variables = {}
+            for v in varlist:
+                try:
+                    (key, value) = v.split('=', 1)
+                except ValueError:
+                    raise InterpreterException('Variable {!r} must have a value separated by equals sign.'.format(v))
+                variables[key.strip()] = value.strip()
+        for k, v in variables.items():
+            if not k or not v:
+                raise InterpreterException('Empty variable name or value')
+            if any(c.isspace() for c in k):
+                raise InterpreterException('Invalid whitespace in variable name "{}"'.format(k))
+            if not isinstance(v, str):
+                raise InterpreterException('variables values must be strings.')
+        return variables
+
     @FeatureNewKwargs('declare_dependency', '0.46.0', ['link_whole'])
     @FeatureNewKwargs('declare_dependency', '0.54.0', ['variables'])
     @permittedKwargs(permitted_kwargs['declare_dependency'])
@@ -2696,12 +2722,7 @@ class Interpreter(InterpreterBase):
         deps = unholder(extract_as_list(kwargs, 'dependencies'))
         compile_args = mesonlib.stringlistify(kwargs.get('compile_args', []))
         link_args = mesonlib.stringlistify(kwargs.get('link_args', []))
-        variables = kwargs.get('variables', {})
-        if not isinstance(variables, dict):
-            raise InterpreterException('variables must be a dict.')
-        if not all(isinstance(v, str) for v in variables.values()):
-            # Because that is how they will come from pkg-config and cmake
-            raise InterpreterException('variables values be strings.')
+        variables = self.extract_variables(kwargs, list_new=True)
         final_deps = []
         for d in deps:
             try:
diff --git a/mesonbuild/modules/pkgconfig.py b/mesonbuild/modules/pkgconfig.py
index 912c9ff9b..38c96a9ca 100644
--- a/mesonbuild/modules/pkgconfig.py
+++ b/mesonbuild/modules/pkgconfig.py
@@ -513,31 +513,17 @@ class PkgConfigModule(ExtensionModule):
 
         deps.remove_dups()
 
-        def parse_variable_list(stringlist):
+        def parse_variable_list(vardict):
             reserved = ['prefix', 'libdir', 'includedir']
             variables = []
-            for var in stringlist:
-                # foo=bar=baz is ('foo', 'bar=baz')
-                l = var.split('=', 1)
-                if len(l) < 2:
-                    raise mesonlib.MesonException('Invalid variable "{}". Variables must be in \'name=value\' format'.format(var))
-
-                name, value = l[0].strip(), l[1].strip()
-                if not name or not value:
-                    raise mesonlib.MesonException('Invalid variable "{}". Variables must be in \'name=value\' format'.format(var))
-
-                # Variable names must not contain whitespaces
-                if any(c.isspace() for c in name):
-                    raise mesonlib.MesonException('Invalid whitespace in assignment "{}"'.format(var))
-
+            for name, value in vardict.items():
                 if name in reserved:
                     raise mesonlib.MesonException('Variable "{}" is reserved'.format(name))
-
                 variables.append((name, value))
-
             return variables
 
-        variables = parse_variable_list(mesonlib.stringlistify(kwargs.get('variables', [])))
+        variables = self.interpreter.extract_variables(kwargs, dict_new=True)
+        variables = parse_variable_list(variables)
 
         pcfile = filebase + '.pc'
         pkgroot = kwargs.get('install_dir', default_install_dir)
@@ -552,7 +538,9 @@ class PkgConfigModule(ExtensionModule):
                                      version, pcfile, conflicts, variables,
                                      False, dataonly)
         res = build.Data(mesonlib.File(True, state.environment.get_scratch_dir(), pcfile), pkgroot)
-        variables = parse_variable_list(mesonlib.stringlistify(kwargs.get('uninstalled_variables', [])))
+        variables = self.interpreter.extract_variables(kwargs, argname='uninstalled_variables', dict_new=True)
+        variables = parse_variable_list(variables)
+
         pcfile = filebase + '-uninstalled.pc'
         self.generate_pkgconfig_file(state, deps, subdirs, name, description, url,
                                      version, pcfile, conflicts, variables,
diff --git a/run_unittests.py b/run_unittests.py
index 708dcb70a..539ecd31b 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -6040,6 +6040,7 @@ class LinuxlikeTests(BasePlatformTests):
         self.assertTrue(libhello_nolib.found())
         self.assertEqual(libhello_nolib.get_link_args(), [])
         self.assertEqual(libhello_nolib.get_compile_args(), [])
+        self.assertEqual(libhello_nolib.get_pkgconfig_variable('foo', {}), 'bar')
 
     def test_pkgconfig_gen_deps(self):
         '''
diff --git a/test cases/common/218 dependency get_variable method/meson.build b/test cases/common/218 dependency get_variable method/meson.build
index 8c189bbe3..9f60836e2 100644
--- a/test cases/common/218 dependency get_variable method/meson.build
+++ b/test cases/common/218 dependency get_variable method/meson.build
@@ -59,3 +59,6 @@ idep = declare_dependency()
 assert(idep.get_variable(pkgconfig : 'foo', cmake : 'foo', configtool : 'foo',
                          default_value : default) == default,
        'something went wrong with an InternalDependency with no variables.')
+
+idep = declare_dependency(variables : ['foo=value'])
+assert(idep.get_variable(internal: 'foo') == 'value')
diff --git a/test cases/common/47 pkgconfig-gen/meson.build b/test cases/common/47 pkgconfig-gen/meson.build
index 8c16cd5bc..4638123cf 100644
--- a/test cases/common/47 pkgconfig-gen/meson.build
+++ b/test cases/common/47 pkgconfig-gen/meson.build
@@ -64,7 +64,8 @@ pkgg.generate(
   name : 'libhello_nolib',
   description : 'A minimalistic pkgconfig file.',
   version : libver,
-  dataonly: true
+  dataonly: true,
+  variables : {'foo': 'bar'},
 )
 
 # Regression test for 2 cases:
diff --git a/test cases/failing/47 pkgconfig variables zero length/test.json b/test cases/failing/47 pkgconfig variables zero length/test.json
index 097fee12e..39ffde4c6 100644
--- a/test cases/failing/47 pkgconfig variables zero length/test.json
+++ b/test cases/failing/47 pkgconfig variables zero length/test.json
@@ -1,7 +1,7 @@
 {
   "stdout": [
     {
-      "line": "test cases/failing/47 pkgconfig variables zero length/meson.build:8:5: ERROR: Invalid variable \"=value\". Variables must be in 'name=value' format"
+      "line": "test cases/failing/47 pkgconfig variables zero length/meson.build:8:5: ERROR: Empty variable name or value"
     }
   ]
 }
diff --git a/test cases/failing/48 pkgconfig variables zero length value/test.json b/test cases/failing/48 pkgconfig variables zero length value/test.json
index 50a35ce97..8aa1bc58f 100644
--- a/test cases/failing/48 pkgconfig variables zero length value/test.json
+++ b/test cases/failing/48 pkgconfig variables zero length value/test.json
@@ -1,7 +1,7 @@
 {
   "stdout": [
     {
-      "line": "test cases/failing/48 pkgconfig variables zero length value/meson.build:8:5: ERROR: Invalid variable \"key=\". Variables must be in 'name=value' format"
+      "line": "test cases/failing/48 pkgconfig variables zero length value/meson.build:8:5: ERROR: Empty variable name or value"
     }
   ]
 }
diff --git a/test cases/failing/49 pkgconfig variables not key value/test.json b/test cases/failing/49 pkgconfig variables not key value/test.json
index cf07e6221..082bd7955 100644
--- a/test cases/failing/49 pkgconfig variables not key value/test.json
+++ b/test cases/failing/49 pkgconfig variables not key value/test.json
@@ -1,7 +1,7 @@
 {
   "stdout": [
     {
-      "line": "test cases/failing/49 pkgconfig variables not key value/meson.build:8:5: ERROR: Invalid variable \"this_should_be_key_value\". Variables must be in 'name=value' format"
+      "line": "test cases/failing/49 pkgconfig variables not key value/meson.build:8:5: ERROR: Variable 'this_should_be_key_value' must have a value separated by equals sign."
     }
   ]
 }