Close #94: Always rebuild apks when aports change

...even if the pkgver and pkgrel have *not* changed. This should
make development much more intuitive. The detection works by looking
at the last modified timestamps, just like `make` does it.

pmb/build/other.py

@@ -22,6 +22,7 @@ import glob
 
 import pmb.chroot
 import pmb.helpers.run
+import pmb.helpers.file
 import pmb.parse.apkindex
 
 
@@ -67,8 +68,10 @@ def copy_to_buildpath(args, package, suffix="native"):
 
 def is_necessary(args, arch, apkbuild, apkindex_path=None):
     """
-    Check if the package has already been built (because abuild's check
-    only works, if it is the same architecture!)
+    Check if the package has already been built. Compared to abuild's check,
+    this check also works for different architectures, and it recognizes
+    changed files in an aport folder, even if the pkgver and pkgrel did not
+    change.
 
     :param arch: package target architecture
     :param apkbuild: from pmb.parse.apkbuild()
@@ -90,8 +93,6 @@ def is_necessary(args, arch, apkbuild, apkindex_path=None):
     if index_data:
         version_old = index_data["version"]
 
-    if version_new == version_old:
-        return False
     if pmb.parse.apkindex.compare_version(version_old,
                                           version_new) == 1:
         logging.warning("WARNING: Package " + package + "-" + version_old +
@@ -99,6 +100,16 @@ def is_necessary(args, arch, apkbuild, apkindex_path=None):
                         " in the APKBUILD. Consider cleaning your package cache" +
                         " (pmbootstrap zap -p) or removing that file and running" +
                         " 'pmbootstrap index'!")
+
+    if version_new != version_old:
+        return True
+
+    # Check if all files in the aport folder have an older timestamp,
+    # than the package.
+    path_target = (os.path.dirname(apkindex_path) + "/" + package + "-" +
+                   version_new + ".apk")
+    path_sources = glob.glob(args.aports + "/" + package + "/*")
+    if pmb.helpers.file.is_up_to_date(path_target, path_sources):
         return False
     return True
 

pmb/helpers/file.py

@@ -17,6 +17,8 @@ You should have received a copy of the GNU General Public License
 along with pmbootstrap.  If not, see <http://www.gnu.org/licenses/>.
 """
 
+import os
+
 
 def replace(path, old, new):
     text = ""
@@ -27,3 +29,23 @@ def replace(path, old, new):
 
     with open(path, 'w') as handle:
         handle.write(text)
+
+
+def is_up_to_date(path_target, path_sources):
+    """
+    Check if a file is up-to-date by comparing the last modified timestamps
+    (just like make does it).
+
+    :param path_target: full path to the target file
+    :param path_sources: list of full paths to the source files
+    """
+
+    lastmod_source = None
+    for path_source in path_sources:
+        lastmod = os.path.getmtime(path_source)
+        if not lastmod_source or lastmod > lastmod_source:
+            lastmod_source = lastmod
+
+    lastmod_target = os.path.getmtime(path_target)
+
+    return lastmod_target >= lastmod_source