1 files changed, 109 insertions, 0 deletions
diff --git a/weed/s3api/s3api_object_handlers_test.go b/weed/s3api/s3api_object_handlers_test.go
index 950dd45f8..cf650a36e 100644
--- a/weed/s3api/s3api_object_handlers_test.go
+++ b/weed/s3api/s3api_object_handlers_test.go
@@ -147,3 +147,112 @@ func TestS3ApiServer_toFilerUrl(t *testing.T) {
 		})
 	}
 }
+
+func TestPartNumberWithRangeHeader(t *testing.T) {
+	tests := []struct {
+		name              string
+		partStartOffset   int64 // Part's start offset in the object
+		partEndOffset     int64 // Part's end offset in the object
+		clientRangeHeader string
+		expectedStart     int64 // Expected absolute start offset
+		expectedEnd       int64 // Expected absolute end offset
+		expectError       bool
+	}{
+		{
+			name:              "No client range - full part",
+			partStartOffset:   1000,
+			partEndOffset:     1999,
+			clientRangeHeader: "",
+			expectedStart:     1000,
+			expectedEnd:       1999,
+			expectError:       false,
+		},
+		{
+			name:              "Range within part - start and end",
+			partStartOffset:   1000,
+			partEndOffset:     1999, // Part size: 1000 bytes
+			clientRangeHeader: "bytes=0-99",
+			expectedStart:     1000, // 1000 + 0
+			expectedEnd:       1099, // 1000 + 99
+			expectError:       false,
+		},
+		{
+			name:              "Range within part - start to end",
+			partStartOffset:   1000,
+			partEndOffset:     1999,
+			clientRangeHeader: "bytes=100-",
+			expectedStart:     1100, // 1000 + 100
+			expectedEnd:       1999, // 1000 + 999 (end of part)
+			expectError:       false,
+		},
+		{
+			name:              "Range suffix - last 100 bytes",
+			partStartOffset:   1000,
+			partEndOffset:     1999, // Part size: 1000 bytes
+			clientRangeHeader: "bytes=-100",
+			expectedStart:     1900, // 1000 + (1000 - 100)
+			expectedEnd:       1999, // 1000 + 999
+			expectError:       false,
+		},
+		{
+			name:              "Range suffix larger than part",
+			partStartOffset:   1000,
+			partEndOffset:     1999, // Part size: 1000 bytes
+			clientRangeHeader: "bytes=-2000",
+			expectedStart:     1000, // Start of part (clamped)
+			expectedEnd:       1999, // End of part
+			expectError:       false,
+		},
+		{
+			name:              "Range start beyond part size",
+			partStartOffset:   1000,
+			partEndOffset:     1999,
+			clientRangeHeader: "bytes=1000-1100",
+			expectedStart:     0,
+			expectedEnd:       0,
+			expectError:       true,
+		},
+		{
+			name:              "Range end clamped to part size",
+			partStartOffset:   1000,
+			partEndOffset:     1999,
+			clientRangeHeader: "bytes=0-2000",
+			expectedStart:     1000, // 1000 + 0
+			expectedEnd:       1999, // Clamped to end of part
+			expectError:       false,
+		},
+		{
+			name:              "Single byte range at start",
+			partStartOffset:   5000,
+			partEndOffset:     9999, // Part size: 5000 bytes
+			clientRangeHeader: "bytes=0-0",
+			expectedStart:     5000,
+			expectedEnd:       5000,
+			expectError:       false,
+		},
+		{
+			name:              "Single byte range in middle",
+			partStartOffset:   5000,
+			partEndOffset:     9999,
+			clientRangeHeader: "bytes=100-100",
+			expectedStart:     5100,
+			expectedEnd:       5100,
+			expectError:       false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Test the actual range adjustment logic from GetObjectHandler
+			startOffset, endOffset, err := adjustRangeForPart(tt.partStartOffset, tt.partEndOffset, tt.clientRangeHeader)
+
+			if tt.expectError {
+				assert.Error(t, err, "Expected error for range %s", tt.clientRangeHeader)
+			} else {
+				assert.NoError(t, err, "Unexpected error for range %s: %v", tt.clientRangeHeader, err)
+				assert.Equal(t, tt.expectedStart, startOffset, "Start offset mismatch")
+				assert.Equal(t, tt.expectedEnd, endOffset, "End offset mismatch")
+			}
+		})
+	}
+}