Revert "Refactor - Remove unused and untested code in utils"

This reverts commit 293a7f5e6add850e2f127dd1680a6e43fb1a6949.

4 files changed, 45 insertions, 9 deletions

diff --git a/pylint/checkers/__init__.py b/pylint/checkers/__init__.py
index d9ed5833c..35831e4c4 100644
--- a/pylint/checkers/__init__.py
+++ b/pylint/checkers/__init__.py
@@ -48,10 +48,10 @@ messages nor reports. XXX not true, emit a 07 report !
 from pylint.checkers.base_checker import BaseChecker, BaseTokenChecker
 from pylint.checkers.deprecated import DeprecatedMixin
 from pylint.checkers.mapreduce_checker import MapReduceMixin
-from pylint.utils import register_plugins
+from pylint.utils import diff_string, register_plugins
 
 
-def table_lines_from_stats(stats, _, columns):
+def table_lines_from_stats(stats, old_stats, columns):
     """get values listed in <columns> from <stats> and <old_stats>,
     and return a formated list of values, designed to be given to a
     ureport.Table object
@@ -60,7 +60,13 @@ def table_lines_from_stats(stats, _, columns):
     for m_type in columns:
         new = stats[m_type]
         new = "%.3f" % new if isinstance(new, float) else str(new)
-        lines += (m_type.replace("_", " "), new, "NC", "NC")
+        old = old_stats.get(m_type)
+        if old is not None:
+            diff_str = diff_string(old, new)
+            old = format(old)
+        else:
+            old, diff_str = "NC", "NC"
+        lines += (m_type.replace("_", " "), new, old, diff_str)
     return lines
 
 
diff --git a/pylint/checkers/base.py b/pylint/checkers/base.py
index c27a91180..9cf68083a 100644
--- a/pylint/checkers/base.py
+++ b/pylint/checkers/base.py
@@ -386,7 +386,7 @@ def _has_abstract_methods(node):
     return len(utils.unimplemented_abstract_methods(node)) > 0
 
 
-def report_by_type_stats(sect, stats, _):
+def report_by_type_stats(sect, stats, old_stats):
     """make a report of
 
     * percentage of different types documented
@@ -415,11 +415,16 @@ def report_by_type_stats(sect, stats, _):
     lines = ("type", "number", "old number", "difference", "%documented", "%badname")
     for node_type in ("module", "class", "method", "function"):
         new = stats[node_type]
+        old = old_stats.get(node_type, None)
+        if old is not None:
+            diff_str = lint_utils.diff_string(old, new)
+        else:
+            old, diff_str = "NC", "NC"
         lines += (
             node_type,
             str(new),
-            "NC",
-            "NC",
+            str(old),
+            diff_str,
             nice_stats[node_type].get("percent_documented", "0"),
             nice_stats[node_type].get("percent_badname", "0"),
         )
diff --git a/pylint/checkers/raw_metrics.py b/pylint/checkers/raw_metrics.py
index b713c4bf6..bb3a519d4 100644
--- a/pylint/checkers/raw_metrics.py
+++ b/pylint/checkers/raw_metrics.py
@@ -20,10 +20,12 @@ from pylint.checkers import BaseTokenChecker
 from pylint.exceptions import EmptyReportError
 from pylint.interfaces import ITokenChecker
 from pylint.reporters.ureports.nodes import Table
+from pylint.utils import diff_string
 
 
-def report_raw_stats(sect, stats, _):
-    """calculate percentage of code / doc / comment / empty"""
+def report_raw_stats(sect, stats, old_stats):
+    """calculate percentage of code / doc / comment / empty
+    """
     total_lines = stats["total_lines"]
     if not total_lines:
         raise EmptyReportError()
@@ -33,7 +35,12 @@ def report_raw_stats(sect, stats, _):
         key = node_type + "_lines"
         total = stats[key]
         percent = float(total * 100) / total_lines
-        lines += (node_type, str(total), "%.2f" % percent, "NC", "NC")
+        old = old_stats.get(key, None)
+        if old is not None:
+            diff_str = diff_string(old, total)
+        else:
+            old, diff_str = "NC", "NC"
+        lines += (node_type, str(total), "%.2f" % percent, str(old), diff_str)
     sect.append(Table(children=lines, cols=5, rheaders=1))
 
 
diff --git a/pylint/utils/utils.py b/pylint/utils/utils.py
index 4b1d7566c..354d5a47a 100644
--- a/pylint/utils/utils.py
+++ b/pylint/utils/utils.py
@@ -34,6 +34,24 @@ def normalize_text(text, line_len=DEFAULT_LINE_LENGTH, indent=""):
     )
 
 
+CMPS = ["=", "-", "+"]
+
+# py3k has no more cmp builtin
+if sys.version_info >= (3, 0):
+
+    def cmp(a, b):  # pylint: disable=redefined-builtin
+        return (a > b) - (a < b)
+
+
+def diff_string(old, new):
+    """given an old and new int value, return a string representing the
+    difference
+    """
+    diff = abs(old - new)
+    diff_str = "%s%s" % (CMPS[cmp(old, new)], diff and ("%.2f" % diff) or "")
+    return diff_str
+
+
 def get_module_and_frameid(node):
     """return the module name and the frame id in the module"""
     frame = node.frame()