fix has_quote detection to handle free-form string values in header c…

…ards (#421) * fix has_quote detection to handle free-form string values in header cards. * add a test case for the free-form string issue * add braces {} for readability * add extra blank lines for pytest linter * fix more 'flake8' complaints * Update fitsio/fitsio_pywrap.c * fix whitespace to match existing style * add CHANGES.md entry --------- Co-authored-by: Matthew R. Becker <[email protected]>
esheldon · Feb 20, 2025 · 94595f1 · 94595f1
1 parent 8cad13b
commit 94595f1
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diff --git a/CHANGES.md b/CHANGES.md
@@ -1,3 +1,10 @@
+version 1.2.6 (not yet released)
+-------------
+
+Bug Fixes
+
+    - Fix bug parsing header cards with free-form strings
+
 version 1.2.5
 -------------
 
@@ -9,7 +16,7 @@ New Features
 
 Bug Fixes
 
-    - Fig bug slicing tables that have TBIT columns
+    - Fix bug slicing tables that have TBIT columns
 
 version 1.2.4
 -------------

diff --git a/fitsio/fitsio_pywrap.c b/fitsio/fitsio_pywrap.c
@@ -4444,8 +4444,18 @@ PyFITSObject_read_header(struct PyFITSObject* self, PyObject* args) {
                         is_string_value=0;
                     }
                 } else {
+                    int j;
                     has_equals = (card[8] == '=') ? 1 : 0;
-                    has_quote = (card[10] == '\'') ? 1 : 0;
+                    has_quote = 0;
+                    // Look for 0 or more space characters followed by a quote character.
+                    for (j=10; j<FLEN_CARD; j++) {
+                        if (card[j] == '\'') {
+                            has_quote = 1;
+                            break;
+                        } else if (card[j] != ' ') {
+                            break;
+                        }
+                    }
                     if (has_equals && has_quote) {
                         is_string_value=1;
                     } else {
@@ -4511,7 +4521,7 @@ PyFITSObject_read_header(struct PyFITSObject* self, PyObject* args) {
 
             } else {
 
-                // if its a stringwe just store it.
+                // if it's a string we just store it.
                 if (is_string_value) {
                     convert_to_ascii(longstr);
                     add_string_to_dict(dict,"value",longstr);

diff --git a/fitsio/tests/test_header.py b/fitsio/tests/test_header.py
@@ -9,6 +9,23 @@
 from ..hdu.base import INVALID_HDR_CHARS
 
 
+def test_free_form_string():
+    with tempfile.TemporaryDirectory() as tmpdir:
+        fname = os.path.join(tmpdir, 'test.fits')
+        with open(fname, 'w') as f:
+            s = ("SIMPLE  =                    T / Standard FITS                                  " + # noqa
+                 "BITPIX  =                   16 / number of bits per data pixel                  " + # noqa
+                 "NAXIS   =                    0 / number of data axes                            " + # noqa
+                 "EXTEND  =                    T / File contains extensions                       " + # noqa
+                 "PHOTREF =   'previous MegaCam' / Source: cum.photcat                            " + # noqa
+                 "EXTRA   =                    7 / need another line following PHOTREF            " + # noqa
+                 "END                                                                             " # noqa
+                 )
+            f.write(s + ' ' * (2880-len(s)))
+        hdr = read_header(fname)
+        assert hdr['PHOTREF'] == 'previous MegaCam'
+
+
 def test_add_delete_and_update_records():
     # Build a FITSHDR from a few records (no need to write on disk)
     # Record names have to be in upper case to match with FITSHDR.add_record