From c44d92e3cd7318c9916206bb808aa18e60ba771f Mon Sep 17 00:00:00 2001
From: IMGillusion <tigillusion2022@gmail.com>
Date: Thu, 10 Sep 2026 12:45:55 +0800
Subject: [PATCH] fix(#459): repair one-case suffix acronyms to all-caps

Gated on the SUFFIX role; exceptions map consulted first so md/phd keep their special casing. R4 example added; corpus regenerated.
---
 docs/design/rules.md                  |  1 +
 nameparser/_render.py                 | 10 ++++++++
 tests/test_capitalization.py          | 33 +++++++++++++++++++++++++++
 tools/differential/corpus_rules.jsonl |  1 +
 4 files changed, 45 insertions(+)

diff --git a/docs/design/rules.md b/docs/design/rules.md
index ba455a15..e60a8fe4 100644
--- a/docs/design/rules.md
+++ b/docs/design/rules.md
@@ -1676,6 +1676,7 @@ R4. Rationale: case repair is a display concern, applied only on
       "ANH DO"                    →  capitalized="Anh Do"
       "anh van do"                →  capitalized="Anh Van Do"
       "john smith phd"            →  capitalized="John Smith Ph.D."
+      "john smith mba"            →  capitalized="John Smith MBA"
       "juan de la vega"           →  capitalized="Juan de la Vega"  · boundary
     Accepted: the clause reaches a part the parser read. A field
     spliced in as raw text after the parse carries no reading of its
diff --git a/nameparser/_render.py b/nameparser/_render.py
index bf3786ca..6952af19 100644
--- a/nameparser/_render.py
+++ b/nameparser/_render.py
@@ -247,6 +247,16 @@ def _cap_word(word: str, role: Role, tags: frozenset[str],
         exception = lex.capitalization_exceptions_map.get(key)
         if exception is not None:
             return exception
+    # A credential acronym the exceptions map doesn't carry (mba, jd,
+    # qc, mp, ...) is an initialism, not a word to title-case. The map
+    # only special-cases the five that need non-all-caps spelling
+    # (md, phd, ii, iii, iv); every other suffix_acronyms entry is
+    # all-caps by definition, so a one-case name repairs to the
+    # acronym's caps instead of 'Mba' (#459). Gated on the SUFFIX role
+    # so a word that is a family name only happens to be in the
+    # vocabulary (anh van DO) still repairs as an ordinary name word.
+    if role is Role.SUFFIX and normalized.replace(".", "") in lex.suffix_acronyms:
+        return word.upper()
     if _MAC.match(word):
         return _MAC.sub(
             lambda m: m.group(1).capitalize() + m.group(2).capitalize(),
diff --git a/tests/test_capitalization.py b/tests/test_capitalization.py
index 4c8f0576..0ba500a2 100644
--- a/tests/test_capitalization.py
+++ b/tests/test_capitalization.py
@@ -110,6 +110,39 @@ def test_capitalize_suffix_acronym_with_dots(self) -> None:
         hn.capitalize()
         self.assertEqual(hn.suffix, 'M.D.')
 
+    # A credential acronym the exceptions map doesn't carry is an
+    # initialism, so a one-case suffix repairs to all-caps instead of
+    # title-case (issue #459).
+    def test_capitalize_suffix_acronym_is_all_caps(self) -> None:
+        for src, expect in [
+            ('JOHN SMITH MBA', 'John Smith MBA'),
+            ('john smith jd', 'John Smith JD'),
+            ('JOSE LUIS CPA', 'Jose Luis CPA'),
+            ('john smith pmp', 'John Smith PMP'),
+        ]:
+            hn = HumanName(src)
+            hn.capitalize()
+            self.m(str(hn), expect, hn)
+
+    # The exceptions map's five keep their special casing; the new
+    # all-caps path must not shadow them (#459).
+    def test_capitalize_exceptions_still_win_over_acronyms(self) -> None:
+        for src, expect in [
+            ('john smith md', 'John Smith M.D.'),
+            ('john smith phd', 'John Smith Ph.D.'),
+        ]:
+            hn = HumanName(src)
+            hn.capitalize()
+            self.m(str(hn), expect, hn)
+
+    # A word in the acronym vocabulary that parses as a family name
+    # still repairs as an ordinary name word, not an acronym (#459).
+    def test_capitalize_family_name_in_acronym_vocab_stays_title_case(self) -> None:
+        hn = HumanName('anh van do')
+        hn.capitalize()
+        self.m(str(hn), 'Anh Van Do', hn)
+
+
     # Leaving already-capitalized names alone
     def test_no_change_to_mixed_chase(self) -> None:
         hn = HumanName('Shirley Maclaine')
diff --git a/tools/differential/corpus_rules.jsonl b/tools/differential/corpus_rules.jsonl
index b30b894f..79c7a7c1 100644
--- a/tools/differential/corpus_rules.jsonl
+++ b/tools/differential/corpus_rules.jsonl
@@ -247,6 +247,7 @@
 "de la Vega y Santos Juan"
 "de los Santos"
 "ibn Awf abdul Rahman"
+"john smith mba"
 "john smith phd"
 "juan de la vega"
 "juan mcdonald"