filesystem: sort guided cases on available size

subiquity/common/filesystem/sizes.py

@@ -115,6 +115,7 @@ def calculate_guided_resize(part_min: int, part_size: int, install_min: int,
     raw_recommended = math.ceil(resize_window * ratio) + other_min
     recommended = align_up(raw_recommended, part_align)
     return GuidedResizeValues(
+            install_max=plausible_free_space,
             minimum=other_min, recommended=recommended, maximum=other_max)
 
 

subiquity/common/filesystem/tests/test_sizes.py

@@ -97,6 +97,7 @@ class TestCalculateGuidedResize(unittest.TestCase):
         actual = calculate_guided_resize(
                 part_min=8 << 30, part_size=100 << 30, install_min=size)
         expected = GuidedResizeValues(
+                install_max=(100 << 30) - size,
                 minimum=size, recommended=50 << 30, maximum=(100 << 30) - size)
         self.assertEqual(expected, actual)
 
@@ -104,6 +105,7 @@ class TestCalculateGuidedResize(unittest.TestCase):
         actual = calculate_guided_resize(
                 part_min=40 << 30, part_size=240 << 30, install_min=10 << 30)
         expected = GuidedResizeValues(
+                install_max=190 << 30,
                 minimum=50 << 30, recommended=200 << 30, maximum=230 << 30)
         self.assertEqual(expected, actual)
 

subiquity/common/types.py

@@ -333,6 +333,7 @@ class StorageResponseV2:
 
 @attr.s(auto_attribs=True)
 class GuidedResizeValues:
+    install_max: int
     minimum: int
     recommended: int
     maximum: int

subiquity/server/controllers/filesystem.py

@@ -360,19 +360,18 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
         Results are sorted by the size of the space potentially available to
         the install."""
 
-        possible = []
+        scenarios = []
         install_min = self.calculate_suggested_install_min()
 
         for disk in self.get_guided_disks(with_reformatting=True):
-            possible.append(GuidedStorageTargetReformat(disk_id=disk.id))
+            reformat = GuidedStorageTargetReformat(disk_id=disk.id)
+            scenarios.append((disk.size, reformat))
 
         for disk in self.get_guided_disks(with_reformatting=False):
             gap = gaps.largest_gap(disk)
-            # FIXME this gap size check can mean that a disk that is
+            if gap is not None and gap.size >= install_min:
-            # accepted is ignored by use_gap
+                use_gap = GuidedStorageTargetUseGap(disk_id=disk.id, gap=gap)
-            if gap is not None and gap.size > install_min:
+                scenarios.append((gap.size, use_gap))
-                possible.append(GuidedStorageTargetUseGap(
-                        disk_id=disk.id, gap=gap))
 
         for disk in self.get_guided_disks(check_boot=False):
             part_align = disk.alignment_data().part_align
@@ -381,11 +380,12 @@ class FilesystemController(SubiquityController, FilesystemManipulator):
                         partition.estimated_min_size, partition.size,
                         install_min, part_align=part_align)
                 if vals is not None:
-                    possible.append(
+                    resize = GuidedStorageTargetResize.from_recommendations(
-                        GuidedStorageTargetResize.from_recommendations(
+                            partition, vals)
-                                partition, vals))
+                    scenarios.append((vals.install_max, resize))
-        # FIXME sort at the end
+
-        return GuidedStorageResponseV2(possible=possible)
+        scenarios.sort(reverse=True, key=lambda x: x[0])
+        return GuidedStorageResponseV2(possible=[s[1] for s in scenarios])
 
     async def v2_guided_POST(self, data: GuidedChoiceV2) \
             -> GuidedStorageResponseV2: