Separate csv and tsv function and remove use of sniff

Csv.sniff could cause random characters or spaces to be used
as the delimiter. Separating  these functions and using a hard coded
dialect fixes this display problem.

Author: AddisonSchiller

mfr/extensions/tabular/libs/__init__.py

@@ -8,6 +8,11 @@ def csv_stdlib():
     return csv_stdlib
 
 
+def tsv_stdlib():
+    from ..libs.stdlib_tools import tsv_stdlib
+    return tsv_stdlib
+
+
 def csv_pandas():
     from ..libs.panda_tools import csv_pandas
     return csv_pandas

mfr/extensions/tabular/libs/stdlib_tools.py

@@ -1,26 +1,45 @@
 import re
 import csv
 
-from mfr.extensions.tabular.exceptions import EmptyTableError, TabularRendererError
 from mfr.extensions.tabular import utilities
+from mfr.extensions.tabular.exceptions import EmptyTableError, TabularRendererError
 
 
 def csv_stdlib(fp):
-    """Read and convert a csv file to JSON format using the python standard library
-    :param fp: File pointer object
-    :return: tuple of table headers and data
-    """
-    data = fp.read(2048)
+    data = fp.seek(2048)
     fp.seek(0)
+    # set the dialect instead of sniffing for it.
+    # sniffing can cause things like spaces or characters to be the delimiter
+    dialect = csv.excel
+    try:
+        _set_dialect_quote_attrs(dialect, data)
+    except:
+        # if this errors it is not an exception
+        pass
 
+    reader = csv.DictReader(fp, dialect=dialect)
+    return parse_stdlib(reader)
+
+def tsv_stdlib(fp):
+    data = fp.seek(2048)
+    fp.seek(0)
+    # set the dialect instead of sniffing for it.
+    # sniffing can cause things like spaces or characters to be the delimiter
+    dialect = csv.excel_tab
     try:
-        dialect = csv.Sniffer().sniff(data)
-    except csv.Error:
-        dialect = csv.excel
-    else:
         _set_dialect_quote_attrs(dialect, data)
+    except:
+        # if this errors it is not an exception
+        pass
 
     reader = csv.DictReader(fp, dialect=dialect)
+    return parse_stdlib(reader)
+
+def parse_stdlib(reader):
+    """Read and convert a csv like file to JSON format using the python standard library
+    :param fp: File pointer object
+    :return: tuple of table headers and data
+    """
     columns = []
     # update the reader field names to avoid duplicate column names when performing row extraction
     for idx, fieldname in enumerate(reader.fieldnames or []):

mfr/extensions/tabular/settings.py

@@ -10,7 +10,7 @@
 
 LIBS = config.get('LIBS', {
     '.csv': [libs.csv_stdlib],
-    '.tsv': [libs.csv_stdlib],
+    '.tsv': [libs.tsv_stdlib],
     '.gsheet': [libs.xlsx_xlrd],
     '.xlsx': [libs.xlsx_xlrd],
     '.xls': [libs.xlsx_xlrd],