From 67f306f059d6caba37556b35c53602057fc3cd2c Mon Sep 17 00:00:00 2001
From: Matthew Newville <newville@cars.uchicago.edu>
Date: Sun, 5 Mar 2023 21:47:14 -0600
Subject: [PATCH] ENH: better handling of non-numeric value in gformat()

Closes: #845
---
 lmfit/printfuncs.py      | 5 +++++
 tests/test_printfuncs.py | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/lmfit/printfuncs.py b/lmfit/printfuncs.py
index 520536a61..d77e4ab48 100644
--- a/lmfit/printfuncs.py
+++ b/lmfit/printfuncs.py
@@ -58,10 +58,15 @@ def gformat(val, length=11):
     Positive values will have leading blank.
 
     """
+    if val is None or isinstance(val, bool):
+        return f'{repr(val):>{length}s}'
     try:
         expon = int(log10(abs(val)))
     except (OverflowError, ValueError):
         expon = 0
+    except TypeError:
+        return f'{repr(val):>{length}s}'
+
     length = max(length, 7)
     form = 'e'
     prec = length - 7
diff --git a/tests/test_printfuncs.py b/tests/test_printfuncs.py
index b41bf7d2e..7b8f13417 100644
--- a/tests/test_printfuncs.py
+++ b/tests/test_printfuncs.py
@@ -306,11 +306,11 @@ def test_report_modelpars(fitresult):
 
 
 def test_report_parvalue_non_numeric(fitresult):
-    """Verify that a non-numeric value is caught (can this ever happens?)."""
+    """Verify that a non-numeric value is handled gracefully."""
     fitresult.params['center'].value = None
     fitresult.params['center'].stderr = None
     report = fitresult.fit_report()
-    assert 'center:     Non Numeric Value?' in report
+    assert len(report) > 50
 
 
 def test_report_zero_value_spercent(fitresult):