Introduce the vcs module

Every once in a while, users ask how they can best achieve to get access
to their current git HEAD, so we provide a module that does it for them.

[ChangeLog] Added the vcs module to provide VCS repository information.
Git and Subversion are supported initially.

Change-Id: Ib425547bf9f04406cda35bf81bcb878f6ea4b9ce
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

1 files changed, 153 insertions, 0 deletions

diff --git a/share/qbs/modules/vcs/vcs-module.qbs b/share/qbs/modules/vcs/vcs-module.qbs
new file mode 100644
index 000000000..290547713
--- /dev/null
+++ b/share/qbs/modules/vcs/vcs-module.qbs
@@ -0,0 +1,153 @@
+import qbs
+import qbs.File
+import qbs.FileInfo
+import qbs.Process
+import qbs.TextFile
+import qbs.Utilities
+
+Module {
+    property string type: typeProbe.type
+    property string repoDir: project.sourceDirectory
+    property string toolFilePath: {
+        if (type === "git")
+            return "git";
+        if (type === "svn")
+            return "svn";
+    }
+
+    property string headerFileName: "vcs-repo-state.h"
+    readonly property string repoState: gitProbe.repoState || subversionProbe.repoState
+
+    // Internal
+    readonly property string includeDir: FileInfo.joinPaths(product.buildDirectory, "vcs-include")
+    readonly property string metaDataBaseDir: typeProbe.metaDataBaseDir
+
+    PropertyOptions {
+        name: "type"
+        allowedValues: ["git", "svn"]
+        description: "the version control system your project is using"
+    }
+
+    Depends { name: "cpp"; condition: headerFileName }
+    Properties {
+        condition: headerFileName
+        cpp.includePaths: [includeDir]
+    }
+
+    Probe {
+        id: typeProbe
+
+        property string tool: toolFilePath
+        property string theRepoDir: repoDir
+
+        property string type
+        property string metaDataBaseDir
+
+        configure: {
+            var detector = new Process();
+            try {
+                detector.setWorkingDirectory(theRepoDir);
+                if (detector.exec(tool || "git", ["rev-parse", "--git-dir"]) === 0) {
+                    found = true;
+                    type = "git";
+                    metaDataBaseDir = detector.readStdOut().trim();
+                    return;
+                }
+                if (detector.exec(tool || "svn",
+                                  ["info", "--show-item", "wc-root", "--no-newline"]) === 0) {
+                    found = true
+                    type = "svn";
+                    metaDataBaseDir = FileInfo.joinPaths(detector.readStdOut(), ".svn");
+                    return;
+                } else if (detector.exec(tool || "svn", ["info"]) === 0) {
+                    if (detector.exec(tool || "svn", ["--version", "--quiet"]) === 0
+                            && Utilities.versionCompare(detector.readStdOut().trim(), "1.9") < 0) {
+                        throw "svn too old, version >= 1.9 required";
+                    }
+                }
+            } finally {
+                detector.close();
+            }
+        }
+    }
+
+    Probe {
+        id: gitProbe
+        condition: type === "git"
+
+        property string tool: toolFilePath
+        property string theRepoDir: repoDir
+        property string filePath: FileInfo.joinPaths(metaDataBaseDir, "logs/HEAD")
+        property var timestamp: File.lastModified(filePath)
+
+        property string repoState
+
+        configure: {
+            if (!File.exists(filePath))
+                return; // No commits yet.
+            var proc = new Process();
+            try {
+                proc.setWorkingDirectory(theRepoDir);
+                proc.exec(tool, ["describe", "--always", "HEAD"], true);
+                repoState = proc.readStdOut().trim();
+                if (repoState)
+                    found = true;
+            } finally {
+                proc.close();
+            }
+        }
+    }
+
+    Probe {
+        id: subversionProbe
+        condition: type === "svn"
+
+        property string tool: toolFilePath
+        property string theRepoDir: repoDir
+        property string filePath: FileInfo.joinPaths(metaDataBaseDir, "wc.db")
+        property var timestamp: File.lastModified(filePath)
+
+        property string repoState
+
+        configure: {
+            var proc = new Process();
+            try {
+                proc.setWorkingDirectory(theRepoDir);
+                proc.exec(tool, ["info", "-r", "HEAD", "--show-item", "revision", "--no-newline"],
+                          true);
+                repoState = proc.readStdOut();
+                if (repoState)
+                    found = true;
+            } finally {
+                proc.close();
+            }
+        }
+    }
+
+    Rule {
+        condition: repoState && headerFileName
+        multiplex: true
+        Artifact {
+            filePath: FileInfo.joinPaths(product.vcs.includeDir, product.vcs.headerFileName)
+            fileTags: ["hpp"]
+        }
+        prepare: {
+            var cmd = new JavaScriptCommand();
+            cmd.description = "generating " + output.fileName;
+            cmd.highlight = "codegen";
+            cmd.repoState = product.vcs.repoState;
+            cmd.sourceCode = function() {
+                var f = new TextFile(output.filePath, TextFile.WriteOnly);
+                try {
+                    f.writeLine("#ifndef VCS_REPO_STATE_H");
+                    f.writeLine("#define VCS_REPO_STATE_H");
+                    f.writeLine('#define VCS_REPO_STATE "' + repoState + '"')
+                    f.writeLine("#endif");
+                } finally {
+                    f.close();
+                }
+            };
+            return [cmd];
+        }
+    }
+}