Add unspecified FS D leading zeros format

FS D leading zero format (probably form Direct) is an unspecified
coordinate format where all numbers are specified with both leading
and trailing zeros.

gerber/gerber_statements.py

@@ -97,7 +97,14 @@ class FSParamStmt(ParamStmt):
         """
         """
         param = stmt_dict.get('param')
-        zeros = 'leading' if stmt_dict.get('zero') == 'L' else 'trailing'
+
+        if stmt_dict.get('zero') == 'L':
+            zeros = 'leading'
+        elif stmt_dict.get('zero') == 'T':
+            zeros = 'trailing'
+        else:
+            zeros = 'none'
+
         notation = 'absolute' if stmt_dict.get('notation') == 'A' else 'incremental'
         fmt = tuple(map(int, stmt_dict.get('x')))
         return cls(param, zeros, notation, fmt)
@@ -117,7 +124,7 @@ class FSParamStmt(ParamStmt):
             Parameter.
 
         zero_suppression : string
-            Zero-suppression mode. May be either 'leading' or 'trailing'
+            Zero-suppression mode. May be either 'leading', 'trailing' or 'none' (all zeros are present)
 
         notation : string
             Notation mode. May be either 'absolute' or 'incremental'

gerber/rs274x.py

@@ -139,12 +139,9 @@ class GerberParser(object):
     NUMBER = r"[\+-]?\d+"
     DECIMAL = r"[\+-]?\d+([.]?\d+)?"
     STRING = r"[a-zA-Z0-9_+\-/!?<>”’(){}.\|&@# :]+"
-    NAME = r"[a-zA-Z_$][a-zA-Z_$0-9]+"
-    FUNCTION = r"G\d{2}"
+    NAME = r"[a-zA-Z_$\.][a-zA-Z_$\.0-9+\-]+"
 
-    COORD_OP = r"D[0]?[123]"
-
-    FS = r"(?P<param>FS)(?P<zero>(L|T))?(?P<notation>(A|I))X(?P<x>[0-7][0-7])Y(?P<y>[0-7][0-7])"
+    FS = r"(?P<param>FS)(?P<zero>(L|T|D))?(?P<notation>(A|I))X(?P<x>[0-7][0-7])Y(?P<y>[0-7][0-7])"
     MO = r"(?P<param>MO)(?P<mo>(MM|IN))"
     LP = r"(?P<param>LP)(?P<lp>(D|C))"
     AD_CIRCLE = r"(?P<param>AD)D(?P<d>\d+)(?P<shape>C)[,]?(?P<modifiers>[^,]*)?"

gerber/utils.py

@@ -54,7 +54,7 @@ def parse_gerber_value(value, format=(2, 5), zero_suppression='trailing'):
         (number of integer-part digits, number of decimal-part digits)
 
     zero_suppression : string
-        Zero-suppression mode. May be 'leading' or 'trailing'
+        Zero-suppression mode. May be 'leading', 'trailing' or 'none'
 
     Returns
     -------
@@ -82,11 +82,14 @@ def parse_gerber_value(value, format=(2, 5), zero_suppression='trailing'):
     if negative:
         value = value.lstrip('-')
 
+    missing_digits = MAX_DIGITS - len(value)
 
-    digits = list('0' * MAX_DIGITS)
-    offset = 0 if zero_suppression == 'trailing' else (MAX_DIGITS - len(value))
-    for i, digit in enumerate(value):
-        digits[i + offset] = digit
+    if zero_suppression == 'trailing':
+        digits = list(value + ('0' * missing_digits))
+    elif zero_suppression == 'leading':
+        digits = list(('0' * missing_digits) + value)
+    else:
+        digits = list(value)
 
     result = float(''.join(digits[:integer_digits] + ['.'] + digits[integer_digits:]))
     return -result if negative else result
@@ -114,7 +117,7 @@ def write_gerber_value(value, format=(2, 5), zero_suppression='trailing'):
         (number of integer-part digits, number of decimal-part digits)
 
     zero_suppression : string
-        Zero-suppression mode. May be 'leading' or 'trailing'
+        Zero-suppression mode. May be 'leading', 'trailing' or 'none'
 
     Returns
     -------
@@ -150,7 +153,7 @@ def write_gerber_value(value, format=(2, 5), zero_suppression='trailing'):
     if zero_suppression == 'trailing':
         while digits and digits[-1] == '0':
             digits.pop()
-    else:
+    elif zero_suppression == 'leading':
         while digits and digits[0] == '0':
             digits.pop(0)