Qt support: Fix possible command line length issue with qmlimportscanner

When there's a lot of QML files, we can hit the dreaded Windows limit for
maximum command line length. Detect this condition and call the tool
repeatedly if necessary.

Fixes: QBS-1633
Change-Id: I20d123d6184eab08c5fa280a7c4811a753275f1f
Reviewed-by: Ivan Komissarov <ABBAPOH@gmail.com>

2 files changed, 22 insertions, 5 deletions

diff --git a/share/qbs/module-providers/Qt/templates/qml.js b/share/qbs/module-providers/Qt/templates/qml.js
index df69034fe..e48c9230e 100644
--- a/share/qbs/module-providers/Qt/templates/qml.js
+++ b/share/qbs/module-providers/Qt/templates/qml.js
@@ -3,14 +3,31 @@ var FileInfo = require("qbs.FileInfo");
 var Process = require("qbs.Process");
 var TextFile = require("qbs.TextFile");
 
-function scannerData(scannerFilePath, qmlFiles, qmlPath)
+function scannerData(scannerFilePath, qmlFiles, qmlPath, targetOS)
 {
     var p;
     try {
         p = new Process();
-        p.exec(scannerFilePath, ["-qmlFiles"].concat(qmlFiles).concat(["-importPath", qmlPath]),
-                true);
-        return JSON.parse(p.readStdOut());
+        if (!targetOS.contains("windows")) {
+            p.exec(scannerFilePath, ["-qmlFiles"].concat(qmlFiles).concat(["-importPath", qmlPath]),
+                    true);
+            return JSON.parse(p.readStdOut());
+        }
+        var data = [];
+        var nextFileIndex = 0;
+        while (nextFileIndex < qmlFiles.length) {
+            var currentFileList = [];
+            var currentFileListStringLength = 0;
+            while (nextFileIndex < qmlFiles.length && currentFileListStringLength < 30000) {
+                var currentFile = qmlFiles[nextFileIndex++];
+                currentFileList.push(currentFile);
+                currentFileListStringLength += currentFile.length;
+            }
+            p.exec(scannerFilePath, ["-qmlFiles"].concat(currentFileList)
+                   .concat(["-importPath", qmlPath]), true);
+            data = data.concat(JSON.parse(p.readStdOut()));
+        }
+        return data;
     } finally {
         if (p)
             p.close();
diff --git a/share/qbs/module-providers/Qt/templates/qml.qbs b/share/qbs/module-providers/Qt/templates/qml.qbs
index f608ba4dd..af7b0fb5f 100644
--- a/share/qbs/module-providers/Qt/templates/qml.qbs
+++ b/share/qbs/module-providers/Qt/templates/qml.qbs
@@ -144,7 +144,7 @@ QtModule {
                     qmlInputs = [];
                 var scannerData = Qml.scannerData(product.Qt.qml.qmlImportScannerFilePath,
                         qmlInputs.map(function(inp) { return inp.filePath; }),
-                        product.Qt.qml.qmlPath);
+                        product.Qt.qml.qmlPath, product.qbs.targetOS);
                 var cppFile;
                 var listFile;
                 try {