pkgconfig: Implement early dependency merging

Due to performance reasons, we have to do the dependency resolution
on the qbspkg-config side, like original pkg-config does.
Otherwise, it is not possible to use GRPC module as it depends on a
bunch of ABSEIL libraries which has a lot of cross-dependencies and
QBS cannot handle them (resolving takes > 10 minutes for a simple
dependency on GRPC).

Change-Id: Ice25f6cea09fe731a511d91891936ba746e5b697
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

5 files changed, 95 insertions, 16 deletions

diff --git a/tests/auto/pkgconfig/testdata/private-dep.pc b/tests/auto/pkgconfig/testdata/private-dep.pc
new file mode 100644
index 000000000..cb401391d
--- /dev/null
+++ b/tests/auto/pkgconfig/testdata/private-dep.pc
@@ -0,0 +1,6 @@
+Name: Requires test package
+Description: Dummy pkgconfig test package for testing Requires/Requires.private
+Version: 1.0.0
+Libs: -L/private-dep/lib -lprivate-dep
+Cflags: -I/private-dep/include
+
diff --git a/tests/auto/pkgconfig/testdata/public-dep.pc b/tests/auto/pkgconfig/testdata/public-dep.pc
new file mode 100644
index 000000000..e450e46f1
--- /dev/null
+++ b/tests/auto/pkgconfig/testdata/public-dep.pc
@@ -0,0 +1,6 @@
+Name: Requires test package
+Description: Dummy pkgconfig test package for testing Requires/Requires.private
+Version: 1.0.0
+Requires.private:
+Libs: -L/public-dep/lib -lpublic-dep
+Cflags: -I/public-dep/include
diff --git a/tests/auto/pkgconfig/testdata/requires-test-merged-static.json b/tests/auto/pkgconfig/testdata/requires-test-merged-static.json
new file mode 100644
index 000000000..2c43b2d40
--- /dev/null
+++ b/tests/auto/pkgconfig/testdata/requires-test-merged-static.json
@@ -0,0 +1,22 @@
+{
+    "Name": "Requires test package",
+    "Description": "Dummy pkgconfig test package for testing Requires/Requires.private",
+    "Version": "1.0.0",
+    "Libs": [
+        {"Type": "LibraryPath", "Value": "/public-dep/lib"},
+        {"Type": "LibraryName", "Value": "public-dep"},
+        {"Type": "LibraryPath", "Value": "/private-dep/lib"},
+        {"Type": "LibraryName", "Value": "private-dep"},
+        {"Type": "LibraryPath", "Value": "/requires-test/lib"},
+        {"Type": "LibraryName", "Value": "requires-test"}
+    ],
+    "Cflags": [
+        {"Type": "IncludePath", "Value": "/public-dep/include"},
+        {"Type": "IncludePath", "Value": "/private-dep/include"},
+        {"Type": "IncludePath", "Value": "/requires-test/include"}
+    ],
+    "Requires": [
+    ],
+    "RequiresPrivate": [
+    ]
+}
diff --git a/tests/auto/pkgconfig/testdata/requires-test-merged.json b/tests/auto/pkgconfig/testdata/requires-test-merged.json
new file mode 100644
index 000000000..88114ba30
--- /dev/null
+++ b/tests/auto/pkgconfig/testdata/requires-test-merged.json
@@ -0,0 +1,19 @@
+{
+    "Name": "Requires test package",
+    "Description": "Dummy pkgconfig test package for testing Requires/Requires.private",
+    "Version": "1.0.0",
+    "Libs": [
+        {"Type": "LibraryPath", "Value": "/public-dep/lib"},
+        {"Type": "LibraryName", "Value": "public-dep"},
+        {"Type": "LibraryPath", "Value": "/requires-test/lib"},
+        {"Type": "LibraryName", "Value": "requires-test"}
+    ],
+    "Cflags": [
+        {"Type": "IncludePath", "Value": "/public-dep/include"},
+        {"Type": "IncludePath", "Value": "/requires-test/include"}
+    ],
+    "Requires": [
+    ],
+    "RequiresPrivate": [
+    ]
+}
diff --git a/tests/auto/pkgconfig/tst_pkgconfig.cpp b/tests/auto/pkgconfig/tst_pkgconfig.cpp
index 96a70d199..1b04d231b 100644
--- a/tests/auto/pkgconfig/tst_pkgconfig.cpp
+++ b/tests/auto/pkgconfig/tst_pkgconfig.cpp
@@ -60,24 +60,32 @@ void TestPkgConfig::initTestCase()
 
 void TestPkgConfig::pkgConfig()
 {
-    QFETCH(QString, fileName);
+    QFETCH(QString, pcFileName);
+    QFETCH(QString, jsonFileName);
     QFETCH(QVariantMap, optionsMap);
 
-    Options options = qbs::Internal::PkgConfigJs::convertOptions(QProcessEnvironment::systemEnvironment(), optionsMap);
+    if (jsonFileName.isEmpty())
+        jsonFileName = pcFileName;
+
+    if (!optionsMap.contains("mergeDependencies"))
+        optionsMap["mergeDependencies"] = false;
+
+    Options options = qbs::Internal::PkgConfigJs::convertOptions(
+            QProcessEnvironment::systemEnvironment(), optionsMap);
     options.searchPaths.push_back(m_workingDataDir.toStdString());
 
     PkgConfig pkgConfig(std::move(options));
 
-    QFile jsonFile(m_workingDataDir + "/" + fileName + ".json");
+    QFile jsonFile(m_workingDataDir + "/" + jsonFileName + ".json");
     QVERIFY(jsonFile.open(QIODevice::ReadOnly));
     QJsonParseError error{};
     const auto json = QJsonDocument::fromJson(jsonFile.readAll(), &error).toVariant().toMap();
     QCOMPARE(error.error, QJsonParseError::NoError);
 
-    const auto &packageOr = pkgConfig.getPackage(fileName.toStdString());
+    const auto &packageOr = pkgConfig.getPackage(pcFileName.toStdString());
     QVERIFY(packageOr.isValid());
     const auto &package = packageOr.asPackage();
-    QCOMPARE(QString::fromStdString(package.baseFileName), fileName);
+    QCOMPARE(QString::fromStdString(package.baseFileName), pcFileName);
     QCOMPARE(QString::fromStdString(package.name), json.value("Name").toString());
     QCOMPARE(QString::fromStdString(package.description), json.value("Description").toString());
     QCOMPARE(QString::fromStdString(package.version), json.value("Version").toString());
@@ -155,20 +163,38 @@ void TestPkgConfig::pkgConfig()
 
 void TestPkgConfig::pkgConfig_data()
 {
-    QTest::addColumn<QString>("fileName");
+    QTest::addColumn<QString>("pcFileName");
+    QTest::addColumn<QString>("jsonFileName");
     QTest::addColumn<QVariantMap>("optionsMap");
 
-    QTest::newRow("non-l-required") << QStringLiteral("non-l-required") << QVariantMap();
-    QTest::newRow("simple") << QStringLiteral("simple") << QVariantMap();
-    QTest::newRow("requires-test") << QStringLiteral("requires-test") << QVariantMap();
-    QTest::newRow("special-flags") << QStringLiteral("special-flags") << QVariantMap();
-    QTest::newRow("system") << QStringLiteral("system") << QVariantMap();
+    QTest::newRow("non-l-required")
+            << QStringLiteral("non-l-required") << QString() << QVariantMap();
+    QTest::newRow("simple")
+            << QStringLiteral("simple") << QString() << QVariantMap();
+    QTest::newRow("requires-test")
+            << QStringLiteral("requires-test") << QString() << QVariantMap();
+    QTest::newRow("requires-test-merged")
+            << QStringLiteral("requires-test")
+            << QStringLiteral("requires-test-merged")
+            << QVariantMap({{"mergeDependencies", true}});
+    QTest::newRow("requires-test-merged-static")
+            << QStringLiteral("requires-test")
+            << QStringLiteral("requires-test-merged-static")
+            << QVariantMap({{"mergeDependencies", true}, {"staticMode", true}});
+    QTest::newRow("special-flags")
+            << QStringLiteral("special-flags") << QString() << QVariantMap();
+    QTest::newRow("system")
+            << QStringLiteral("system") << QString() << QVariantMap();
     QTest::newRow("sysroot")
-            << QStringLiteral("sysroot") << QVariantMap({{"sysroot", "/newroot"}});
-    QTest::newRow("tilde") << QStringLiteral("tilde") << QVariantMap();
-    QTest::newRow("variables") << QStringLiteral("variables") << QVariantMap();
-    QTest::newRow("whitespace") << QStringLiteral("whitespace") << QVariantMap();
-    QTest::newRow("base.name") << QStringLiteral("base.name") << QVariantMap();
+            << QStringLiteral("sysroot") << QString() << QVariantMap({{"sysroot", "/newroot"}});
+    QTest::newRow("tilde")
+            << QStringLiteral("tilde") << QString() << QVariantMap();
+    QTest::newRow("variables")
+            << QStringLiteral("variables") << QString() << QVariantMap();
+    QTest::newRow("whitespace")
+            << QStringLiteral("whitespace") << QString() << QVariantMap();
+    QTest::newRow("base.name")
+            << QStringLiteral("base.name") << QString() << QVariantMap();
 }
 
 void TestPkgConfig::benchSystem()