AgamaProposal: fix bug when partitions are searched but not managed (#…

…1767)

## Problem

When a drive was configured with an empty search for partitions like
this (in which there is no configuration about deleting or resizing the
found partitions)...

```json
{
  "storage": {
    "drives": [
      {
        "partitions": [
          { "search": "*" },
          { "filesystem": { "path": "/" } }
        ]
      }
    ]
  } 
} 
```

...all the matched pre-existing partitions are considered as candidates
to be shrunk.

## Solution

With this fix, partitions with no actions do not generate any SpaceMaker
action.

## Bonus

`AgamaProposal` now returns an exception of type
`Y2Storage::NoDiskSpaceError` when the SpaceMaker fails to find space.
That was the documented behavior, but a generic `Y2Storage::Error` was
returned instead.

## Testing

- Added a new unit test
- Tested manually

service/lib/y2storage/proposal/agama_devices_creator.rb

@@ -125,11 +125,17 @@ def process_devices
       def process_existing_partitionables
         partitions = partitions_for_existing(planned_devices)
 
-        # Check whether there is any chance of getting an unwanted order for the planned partitions
-        # within a disk
-        space_result = space_maker.provide_space(
-          original_graph, partitions: partitions, volume_groups: automatic_vgs
-        )
+        begin
+          # Check whether there is any chance of getting an unwanted order for the planned
+          # partitions within a disk
+          space_result = space_maker.provide_space(
+            original_graph, partitions: partitions, volume_groups: automatic_vgs
+          )
+        rescue Error => e
+          log.info "SpaceMaker was not able to find enough space: #{e}"
+          raise NoDiskSpaceError
+        end
+
         self.devicegraph = space_result[:devicegraph]
         distribution = space_result[:partitions_distribution]
 

service/lib/y2storage/proposal/agama_space_maker.rb

@@ -88,13 +88,22 @@ def delete_actions(config)
       # @return [Array<Y2Storage::SpaceActions::Resize>]
       def resize_actions(config)
         partition_configs = partitions(config).select(&:found_device).select(&:size)
-        partition_configs.map do |part|
-          # Resize actions contain information that is potentially useful for the SpaceMaker even
-          # when they are only about growing and not shrinking
-          min = current_size?(part, :min) ? nil : part.size.min
-          max = current_size?(part, :max) ? nil : part.size.max
-          Y2Storage::SpaceActions::Resize.new(part.found_device.name, min_size: min, max_size: max)
-        end.compact
+        # Resize actions contain information that is potentially useful for the SpaceMaker even
+        # when they are only about growing and not shrinking
+        partition_configs.map { |p| resize_action(p) }.compact
+      end
+
+      # @see #resize_actions
+      #
+      # @param part [Agama::Storage::Configs::Partition]
+      # @return [Y2Storage::SpaceActions::Resize, nil]
+      def resize_action(part)
+        min = current_size?(part, :min) ? nil : part.size.min
+        max = current_size?(part, :max) ? nil : part.size.max
+        # If both min and max are equal to the current device size, there is nothing to do
+        return unless min || max
+
+        Y2Storage::SpaceActions::Resize.new(part.found_device.name, min_size: min, max_size: max)
       end
 
       # @see #resize_actions

service/package/rubygem-agama-yast.changes

@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Thu Nov 14 15:34:17 UTC 2024 - Ancor Gonzalez Sosa <[email protected]>
+
+- Storage: fixed bug when existing partitions were searched at the
+  config but not deleted or resized (gh#agama-project/agama#1767).
+
 -------------------------------------------------------------------
 Thu Nov 14 13:26:23 UTC 2024 - Ancor Gonzalez Sosa <[email protected]>
 

service/test/agama/storage/proposal_test.rb

@@ -580,7 +580,7 @@ def drive(partitions)
         subject.calculate_agama(config)
 
         expect(subject.issues).to include(
-          an_object_having_attributes(description: /A problem ocurred/)
+          an_object_having_attributes(description: /Cannot accommodate/)
         )
       end
     end

service/test/y2storage/agama_proposal_search_test.rb

@@ -214,5 +214,30 @@
         end
       end
     end
+
+    context "when searching existing partitions but not specifying any action on them" do
+      let(:config_json) do
+        {
+          boot:   { configure: false },
+          drives: [
+            {
+              search:     "/dev/vda",
+              partitions: [
+                { search: "*" },
+                { size: "20 GiB", filesystem: { path: "/" } }
+              ]
+            }
+          ]
+        }
+      end
+
+      # Regression test. In the past the proposal tried to resize some partitions due to the
+      # search "*" without actions.
+      it "no partitions are deleted or resized" do
+        expect_any_instance_of(Y2Storage::Partition).to_not receive(:detect_resize_info)
+        # There is no way to make 20 GiB fit without resizing or deleting
+        expect { proposal.propose }.to raise_error(Y2Storage::NoDiskSpaceError)
+      end
+    end
   end
 end