Add Configure-Time Tests for gperf, flex and bison

Configure-Time tests for presence of (required) gperf, bison and flex
are added to configure.pri and configure.json, so that we can decide
early on to skip the build, instead of starting a build that
will fail much later, yield incomprehensible error messages and
make the build of the complete Qt framework fail.

Task-number: QTBUG-52805
Change-Id: I7dab49e6e8672b72901519ad7d88de97197fe587
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

3 files changed, 85 insertions, 0 deletions

diff --git a/configure.json b/configure.json
index e82247ec5..69d261a00 100644
--- a/configure.json
+++ b/configure.json
@@ -67,6 +67,18 @@
             "type": "detectPython2",
             "log": "location"
         },
+        "gperf": {
+            "label": "gperf",
+            "type": "detectGperf"
+        },
+        "bison": {
+            "label": "bison",
+            "type": "detectBison"
+        },
+        "flex": {
+            "label": "flex",
+            "type": "detectFlex"
+        },
         "ninja": {
             "label": "system ninja",
             "type": "detectNinja"
@@ -89,6 +101,21 @@
                 { "type": "varAssign", "name": "QMAKE_PYTHON2", "value": "tests.python2.location" }
             ]
         },
+        "gperf": {
+            "label": "gperf",
+            "condition": "tests.gperf",
+            "output": [ "privateFeature" ]
+        },
+        "bison": {
+            "label": "bison",
+            "condition": "tests.bison",
+            "output": [ "privateFeature" ]
+        },
+        "flex": {
+            "label": "flex",
+            "condition": "tests.flex",
+            "output": [ "privateFeature" ]
+        },
         "embedded": {
             "label": "Embedded build",
             "purpose": "Enables the embedded build configuration.",
@@ -185,6 +212,21 @@
             "type": "warning",
             "condition": "!features.python2",
             "message": "Python version 2 (2.7.5 or later) is required to build QtWebEngine."
+        },
+        {
+            "type": "warning",
+            "condition": "!features.gperf",
+            "message": "gperf is required to build QtWebEngine."
+        },
+        {
+            "type": "warning",
+            "condition": "!features.bison",
+            "message": "bison is required to build QtWebEngine."
+        },
+        {
+            "type": "warning",
+            "condition": "!features.flex",
+            "message": "flex is required to build QtWebEngine."
         }
     ],
 
diff --git a/configure.pri b/configure.pri
index ce36642bb..2d6983354 100644
--- a/configure.pri
+++ b/configure.pri
@@ -41,6 +41,36 @@ defineTest(qtConfTest_detectPython2) {
     return(true)
 }
 
+defineTest(qtConfTest_detectGperf) {
+    gperf = $$qtConfFindInPath("gperf$$EXE_SUFFIX")
+    isEmpty(gperf) {
+        qtLog("Required gperf could not be found.")
+        return(false)
+    }
+    qtLog("Found gperf from path: $$gperf")
+    return(true)
+}
+
+defineTest(qtConfTest_detectBison) {
+    bison = $$qtConfFindInPath("bison$$EXE_SUFFIX")
+    isEmpty(bison) {
+        qtLog("Required bison could not be found.")
+        return(false)
+    }
+    qtLog("Found bison from path: $$bison")
+    return(true)
+}
+
+defineTest(qtConfTest_detectFlex) {
+    flex = $$qtConfFindInPath("flex$$EXE_SUFFIX")
+    isEmpty(flex) {
+        qtLog("Required flex could not be found.")
+        return(false)
+    }
+    qtLog("Found flex from path: $$flex")
+    return(true)
+}
+
 defineTest(qtConfTest_detectNinja) {
     ninja = $$qtConfFindInPath("ninja$$EXE_SUFFIX")
     !isEmpty(ninja) {
diff --git a/mkspecs/features/configure.prf b/mkspecs/features/configure.prf
index c1e919603..a07171b3e 100644
--- a/mkspecs/features/configure.prf
+++ b/mkspecs/features/configure.prf
@@ -24,6 +24,19 @@ defineTest(runConfigure) {
         include($$QTWEBENGINE_OUT_ROOT/qtwebengine-config.pri)
         QT_FOR_CONFIG += webengine-private
 
+        !qtConfig(gperf) {
+            skipBuild("Required gperf could not be found.")
+            return(false)
+        }
+        !qtConfig(bison) {
+            skipBuild("Required bison could not be found.")
+            return(false)
+        }
+        !qtConfig(flex) {
+            skipBuild("Required flex could not be found.")
+            return(false)
+        }
+
         qtConfig(pepper-plugins): WEBENGINE_CONFIG += use_pepper_plugins
         qtConfig(printing-and-pdf): WEBENGINE_CONFIG += use_printing use_pdf
         qtConfig(proprietary-codecs): WEBENGINE_CONFIG += use_proprietary_codecs