Ugly fix for #153

This is a sort of brute-force workaround to avoid #153. Likely not up to
the standard of `fprettify` but 'works-for-me'.
Test amended to cover the corner case, I think.

Author: dbroemmel

fprettify/__init__.py

@@ -1416,6 +1416,8 @@ def replace_relational_single_fline(f_line, cstyle):
     .ne.  <-->  /=
     """
 
+    # keep track of whether the line may be affected
+    line_affected = False
     new_line = f_line
 
     # only act on lines that do contain a relation
@@ -1459,8 +1461,25 @@ def replace_relational_single_fline(f_line, cstyle):
             line_parts[pos] = part
 
         new_line = "".join(line_parts)
+        line_affected = True
 
-    return new_line
+    return new_line, line_affected
+
+
+def replace_relational_lines(lines, cstyle):
+    """
+    format a list of lines - replaces scalar relational
+    operators in logical expressions to either Fortran or C-style
+    by calling original function for single line.
+    """
+
+    new_lines = []
+
+    for f_line in lines:
+        new_line, changed = replace_relational_single_fline(f_line, cstyle)
+        new_lines.append(new_line)
+
+    return new_lines
 
 
 def replace_keywords_single_fline(f_line, case_dict):
@@ -2241,7 +2260,10 @@ def reformat_ffile_combined(
             f_line = f_line.strip(" ")
 
             if impose_replacements:
-                f_line = replace_relational_single_fline(f_line, cstyle)
+                f_line, relation_found = replace_relational_single_fline(f_line, cstyle)
+                if relation_found:
+                    updated_lines = replace_relational_lines(lines, cstyle)
+                    linebreak_pos = get_linebreak_pos(updated_lines, filter_fypp=not indent_fypp)
 
             if impose_case:
                 f_line = replace_keywords_single_fline(f_line, case_dict)