Fix handling of inline scopes in too-many-statements (#1979)

Nested scopes don't reset reset the `too-many-statements` check
state.

Close #1978

5 files changed, 87 insertions, 9 deletions

diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index 4b3443a02..2c685c391 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -188,6 +188,8 @@ Order doesn't matter (not that much, at least ;)
   Added new check `logging-fstring-interpolation`
   Documentation typo fixes
 
+* Mark Roman Miller: fix inline defs in too-many-statements
+
 * Adam Dangoor: contributor
 
 * Gary Tyler McLeod: contributor
diff --git a/ChangeLog b/ChangeLog
index f54ef2f8c..6c413b033 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -227,6 +227,10 @@ Release date: |TBA|
       Close #638
 
     * Updated the default report format to include paths that can be clicked on in some terminals (e.g. iTerm).
+    
+    * Fix inline def behavior with ``too-many-statements`` checker
+
+      Close #1978
 
     * Fix `KeyError` raised when using docparams and NotImplementedError is documented.
 
diff --git a/pylint/checkers/design_analysis.py b/pylint/checkers/design_analysis.py
index cd5a8d631..94482b67a 100644
--- a/pylint/checkers/design_analysis.py
+++ b/pylint/checkers/design_analysis.py
@@ -171,13 +171,18 @@ class MisdesignChecker(BaseChecker):
         self.stats = None
         self._returns = None
         self._branches = None
-        self._stmts = 0
+        self._stmts = None
 
     def open(self):
         """initialize visit variables"""
         self.stats = self.linter.add_stats()
         self._returns = []
         self._branches = defaultdict(int)
+        self._stmts = []
+
+    def _inc_all_stmts(self, amount):
+        for i in range(len(self._stmts)):
+            self._stmts[i] += amount
 
     @decorators.cachedproperty
     def _ignored_argument_names(self):
@@ -260,8 +265,8 @@ class MisdesignChecker(BaseChecker):
         if locnum > self.config.max_locals:
             self.add_message('too-many-locals', node=node,
                              args=(locnum, self.config.max_locals))
-        # init statements counter
-        self._stmts = 1
+        # init new statements counter
+        self._stmts.append(1)
 
     visit_asyncfunctiondef = visit_functiondef
 
@@ -281,9 +286,10 @@ class MisdesignChecker(BaseChecker):
             self.add_message('too-many-branches', node=node,
                              args=(branches, self.config.max_branches))
         # check number of statements
-        if self._stmts > self.config.max_statements:
+        stmts = self._stmts.pop()
+        if stmts > self.config.max_statements:
             self.add_message('too-many-statements', node=node,
-                             args=(self._stmts, self.config.max_statements))
+                             args=(stmts, self.config.max_statements))
 
     leave_asyncfunctiondef = leave_functiondef
 
@@ -298,7 +304,7 @@ class MisdesignChecker(BaseChecker):
         necessary
         """
         if node.is_statement:
-            self._stmts += 1
+            self._inc_all_stmts(1)
 
     def visit_tryexcept(self, node):
         """increments the branches counter"""
@@ -306,12 +312,12 @@ class MisdesignChecker(BaseChecker):
         if node.orelse:
             branches += 1
         self._inc_branch(node, branches)
-        self._stmts += branches
+        self._inc_all_stmts(branches)
 
     def visit_tryfinally(self, node):
         """increments the branches counter"""
         self._inc_branch(node, 2)
-        self._stmts += 2
+        self._inc_all_stmts(2)
 
     @check_messages('too-many-boolean-expressions')
     def visit_if(self, node):
@@ -323,7 +329,7 @@ class MisdesignChecker(BaseChecker):
                             not isinstance(node.orelse[0], If)):
             branches += 1
         self._inc_branch(node, branches)
-        self._stmts += branches
+        self._inc_all_stmts(branches)
 
     def _check_boolean_expressions(self, node):
         """Go through "if" node `node` and counts its boolean expressions
diff --git a/pylint/test/functional/too_many_statements.py b/pylint/test/functional/too_many_statements.py
index 305db8071..b3e2fd796 100644
--- a/pylint/test/functional/too_many_statements.py
+++ b/pylint/test/functional/too_many_statements.py
@@ -58,3 +58,68 @@ def stupid_function(arg): # [too-many-statements]
         print(1)
         print(1)
         print(1)
+
+def long_function_with_inline_def(fake): # [too-many-statements]
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    def an_inline_function(var):
+        return var + var
+    fake = an_inline_function(fake)
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
+    fake += 1
diff --git a/pylint/test/functional/too_many_statements.txt b/pylint/test/functional/too_many_statements.txt
index 255e97ee1..9a8abfc36 100644
--- a/pylint/test/functional/too_many_statements.txt
+++ b/pylint/test/functional/too_many_statements.txt
@@ -1 +1,2 @@
 too-many-statements:5:stupid_function:Too many statements (55/50)
+too-many-statements:62:long_function_with_inline_def:Too many statements (62/50)