Fix every real lint finding and drop degenerate splice fragments

ingestion/tests/test_extract_glyph_order.py

@@ -0,0 +1,79 @@
+from ingestion.extract.glyph_order import find_reading_order_issues, is_reversed_order
+
+
+def test_normal_ltr_span_not_flagged():
+    # ordinary increasing x-origins, as any normal left-to-right span has
+    assert not is_reversed_order([264.7, 269.4, 271.6, 276.3, 278.5])
+
+
+def test_confirmed_page_1373_defect_shape_is_flagged():
+    # exact x-origins read via get_text("rawdict") from physical page 1373's
+    # affected span (" tịx 4 =" reversed) — see docs/pdf-parsing-outlier-catalog.md item 9
+    x_origins = [66.32, 64.17, 61.53, 58.89, 54.14, 51.98, 47.23]
+    assert is_reversed_order(x_origins)
+
+
+def test_single_char_span_not_flagged():
+    assert not is_reversed_order([100.0])
+
+
+def test_empty_span_not_flagged():
+    assert not is_reversed_order([])
+
+
+def test_tied_x_origins_not_flagged_as_reversed():
+    # equal x-origins (e.g. stacked/overlapping glyphs) are not "decreasing"
+    assert not is_reversed_order([100.0, 100.0, 100.0])
+
+
+def test_correctly_ordered_row_not_flagged():
+    row = {(20, 550.9): [(518.0, "n"), (525.2, "h"), (532.6, "i"), (536.8, "e")]}
+    assert find_reading_order_issues(row) == []
+
+
+def test_confirmed_page_714_row_misorder_is_flagged():
+    # reproduces the real page-714 finding: within one PyMuPDF block (20),
+    # 4 line fragments are emitted out of x-order ("quản ", " ộ", "đ tệih",
+    # "n " concatenated) that reconstruct correctly ("...nhiệt độ") when
+    # re-sorted by x-origin — see outlier catalog item 9.
+    row = {
+        (20, 550.9): [
+            (518.06, "n"), (525.20, " "),
+            (546.59, " "), (553.71, "ộ"),
+            (541.84, "đ"), (539.45, " "), (536.81, "t"), (532.59, "ệ"), (529.95, "i"), (525.20, "h"),
+        ]
+    }
+    issues = find_reading_order_issues(row)
+    assert len(issues) == 1
+    assert issues[0].extracted_text != issues[0].corrected_text
+
+
+def test_different_blocks_at_same_y_not_merged():
+    # regression test for a real false positive: two DIFFERENT paragraphs in
+    # different PyMuPDF blocks (a right-column paragraph starting at x=299.4
+    # and a left-column paragraph starting at x=35.4, page 1104) coincide at
+    # the same y — grouping by block index (not a hand-picked x-coordinate
+    # column boundary) is what keeps them from being merged into one "row".
+    # This is the caller's responsibility (scan_reading_order groups by real
+    # PyMuPDF block index); find_reading_order_issues just trusts its input
+    # is already correctly grouped, which these two dict entries demonstrate.
+    row_block_1 = {(1, 70.4): [(299.39, "m"), (306.78, "ô")]}
+    row_block_4 = {(4, 70.4): [(35.43, "d"), (40.18, "e")]}
+    assert find_reading_order_issues(row_block_1) == []
+    assert find_reading_order_issues(row_block_4) == []
+
+
+def test_kerning_jitter_not_flagged_as_reading_order_defect():
+    # regression test for a real false positive found by running against the
+    # actual PDF: "mefloquin" ('l' at x=491.566, 'o' at x=491.471 — a
+    # 0.095pt kerning-driven dip) was previously "corrected" into the wrong
+    # word "mefolquin". A row-level check with no decrease tolerance treats
+    # ordinary kerning as a defect and corrupts already-correct text.
+    row = {
+        (5, 449.7): [
+            (474.865, "m"), (482.161, "e"), (486.284, "f"),
+            (491.566, "l"), (491.471, "o"), (496.126, "q"),
+            (500.781, "u"), (505.436, "i"), (507.982, "n"),
+        ]
+    }
+    assert find_reading_order_issues(row) == []