diff --git a/lib/rubocop/cop/security/compound_hash.rb b/lib/rubocop/cop/security/compound_hash.rb
index d08932f6160..b9ab0656b94 100644
--- a/lib/rubocop/cop/security/compound_hash.rb
+++ b/lib/rubocop/cop/security/compound_hash.rb
@@ -30,8 +30,8 @@ module Security
       class CompoundHash < Base
         COMBINATOR_IN_HASH_MSG = 'Use `[...].hash` instead of combining hash values manually.'
         MONUPLE_HASH_MSG =
-          'Delegate hash directly without wrapping in an array when only using a single value'
-        REDUNDANT_HASH_MSG = 'Calling .hash on elements of a hashed array is redundant'
+          'Delegate hash directly without wrapping in an array when only using a single value.'
+        REDUNDANT_HASH_MSG = 'Calling .hash on elements of a hashed array is redundant.'
 
         # @!method hash_method_definition?(node)
         def_node_matcher :hash_method_definition?, <<~PATTERN
diff --git a/lib/rubocop/cop/style/conditional_assignment.rb b/lib/rubocop/cop/style/conditional_assignment.rb
index ebb17ab62f7..7afdadf6ad6 100644
--- a/lib/rubocop/cop/style/conditional_assignment.rb
+++ b/lib/rubocop/cop/style/conditional_assignment.rb
@@ -214,7 +214,7 @@ class ConditionalAssignment < Base
         extend AutoCorrector
 
         MSG = 'Use the return of the conditional for variable assignment and comparison.'
-        ASSIGN_TO_CONDITION_MSG = 'Assign variables inside of conditionals'
+        ASSIGN_TO_CONDITION_MSG = 'Assign variables inside of conditionals.'
         VARIABLE_ASSIGNMENT_TYPES = %i[casgn cvasgn gvasgn ivasgn lvasgn].freeze
         ASSIGNMENT_TYPES = VARIABLE_ASSIGNMENT_TYPES + %i[and_asgn or_asgn op_asgn masgn].freeze
         LINE_LENGTH = 'Layout/LineLength'
diff --git a/spec/rubocop/cop/alignment_corrector_spec.rb b/spec/rubocop/cop/alignment_corrector_spec.rb
index c752ea9116b..a1de990133c 100644
--- a/spec/rubocop/cop/alignment_corrector_spec.rb
+++ b/spec/rubocop/cop/alignment_corrector_spec.rb
@@ -10,7 +10,7 @@
           expect_offense(<<~RUBY)
             # >> 2
               42
-              ^^ Indent this node
+              ^^ Indent this node.
           RUBY
 
           expect_correction(<<~RUBY, loop: false)
@@ -25,7 +25,7 @@
           expect_offense(<<~RUBY)
             # << 3
                 42
-                ^^ Indent this node
+                ^^ Indent this node.
           RUBY
 
           expect_correction(<<~RUBY, loop: false)
@@ -44,7 +44,7 @@
         expect_offense(<<~RUBY)
           # >> #{column_delta}
           begin
-          ^^^^^ Indent this node
+          ^^^^^ Indent this node.
             #{start_heredoc}
           a
           b
@@ -80,7 +80,7 @@
         expect_offense(<<~RUBY)
           # >> 2
           begin
-          ^^^^^ Indent this node
+          ^^^^^ Indent this node.
             <<DOC
           single line
           DOC
@@ -103,7 +103,7 @@
         expect_offense(<<~RUBY)
           # >> 2
           begin
-          ^^^^^ Indent this node
+          ^^^^^ Indent this node.
             dstr =
           'a
           b
diff --git a/spec/rubocop/cop/security/compound_hash_spec.rb b/spec/rubocop/cop/security/compound_hash_spec.rb
index d9856303ffd..94482f859eb 100644
--- a/spec/rubocop/cop/security/compound_hash_spec.rb
+++ b/spec/rubocop/cop/security/compound_hash_spec.rb
@@ -50,7 +50,7 @@ def object.hash
     expect_offense(<<~RUBY)
       def hash
         [1].hash
-        ^^^^^^^^ Delegate hash directly without wrapping in an array when only using a single value
+        ^^^^^^^^ Delegate hash directly without wrapping in an array when only using a single value.
       end
     RUBY
   end
@@ -58,7 +58,7 @@ def hash
   it 'registers an offense if .hash is called on any elements of a hashed array' do
     expect_offense(<<~RUBY)
       [1, 2.hash, 3].hash
-          ^^^^^^ Calling .hash on elements of a hashed array is redundant
+          ^^^^^^ Calling .hash on elements of a hashed array is redundant.
     RUBY
   end
 
diff --git a/spec/rubocop/cop/style/conditional_assignment_assign_in_condition_spec.rb b/spec/rubocop/cop/style/conditional_assignment_assign_in_condition_spec.rb
index 3903c012a7e..ecc8b67cb05 100644
--- a/spec/rubocop/cop/style/conditional_assignment_assign_in_condition_spec.rb
+++ b/spec/rubocop/cop/style/conditional_assignment_assign_in_condition_spec.rb
@@ -5,7 +5,7 @@
     it 'registers an offense assigning any variable type to ternary' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = foo? ? 1 : 2
-        ^{variable}^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
       RUBY
 
       expect_correction(<<~RUBY)
@@ -16,7 +16,7 @@
     it 'registers an offense assigning any variable type to if else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = if foo
-        ^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         1
                       else
                         2
@@ -35,7 +35,7 @@
     it 'registers an offense assigning any variable type to if elsif else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = if foo
-        ^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         1
                       elsif baz
                         2
@@ -58,7 +58,7 @@
     it 'registers an offense assigning any variable type to if else with multiple assignment' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable}, %{variable} = if foo
-        ^{variable}^^^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         something
                       else
                         something_else
@@ -85,7 +85,7 @@
     it 'registers an offense assigning any variable type to unless else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = unless foo
-        ^{variable}^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^^^^^ Assign variables inside of conditionals.
                         1
                       else
                         2
@@ -104,7 +104,7 @@
     it 'registers an offense for assigning any variable type to case when' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = case foo
-        ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals.
                       when "a"
                         1
                       when "b"
@@ -130,7 +130,7 @@
       it 'registers an offense for assigning any variable type to case in' do
         expect_offense(<<~RUBY, variable: variable)
           %{variable} = case foo
-          ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals
+          ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals.
                         in "a"
                           1
                         in "b"
@@ -168,7 +168,7 @@
     it 'registers an offense for any assignment to ternary' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} (foo? ? 1 : 2)
-        ^^^^^{assignment}^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
       RUBY
 
       expect_correction(<<~RUBY)
@@ -179,7 +179,7 @@
     it 'registers an offense any assignment to if else' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} if foo
-        ^^^^^{assignment}^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^ Assign variables inside of conditionals.
                         1
                       else
                         2
@@ -206,7 +206,7 @@
     it 'registers an offense for any assignment to unless else' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} unless foo
-        ^^^^^{assignment}^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^^^^^ Assign variables inside of conditionals.
                         1
                       else
                         2
@@ -225,7 +225,7 @@
     it 'registers an offense any assignment to case when' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} case foo
-        ^^^^^{assignment}^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^^^ Assign variables inside of conditionals.
                       when "a"
                         1
                       else
@@ -258,7 +258,7 @@
     it 'assigning any variable type to a multiline if else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = if foo
-        ^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         something
                         1
                       else
@@ -281,7 +281,7 @@
     it 'assigning any variable type to an if else with multiline in one branch' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = if foo
-        ^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         1
                       else
                         something_else
@@ -302,7 +302,7 @@
     it 'assigning any variable type to a multiline if elsif else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = if foo
-        ^{variable}^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^ Assign variables inside of conditionals.
                         something
                         1
                       elsif bar
@@ -337,7 +337,7 @@
     it 'assigning any variable type to a multiline unless else' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = unless foo
-        ^{variable}^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^^^^^ Assign variables inside of conditionals.
                         something
                         1
                       else
@@ -360,7 +360,7 @@
     it 'assigning any variable type to a multiline case when' do
       expect_offense(<<~RUBY, variable: variable)
         %{variable} = case foo
-        ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals
+        ^{variable}^^^^^^^^^^^ Assign variables inside of conditionals.
                       when "a"
                         something
                         1
@@ -455,7 +455,7 @@
     it 'any assignment to a multiline if else' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} if foo
-        ^^^^^{assignment}^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^ Assign variables inside of conditionals.
                         something
                         1
                       else
@@ -478,7 +478,7 @@
     it 'any assignment to a multiline unless else' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} unless foo
-        ^^^^^{assignment}^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^^^^^ Assign variables inside of conditionals.
                         something
                         1
                       else
@@ -501,7 +501,7 @@
     it 'any assignment to a multiline case when' do
       expect_offense(<<~RUBY, assignment: assignment)
         bar %{assignment} case foo
-        ^^^^^{assignment}^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^{assignment}^^^^^^^^^ Assign variables inside of conditionals.
                       when "a"
                         something
                         1
@@ -567,7 +567,7 @@
     it 'corrects assignment to an if else condition' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 1
               else
                 2
@@ -586,7 +586,7 @@
     it 'corrects assignment to an if elsif else condition' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 1
               elsif foobar
                 2
@@ -609,7 +609,7 @@
     it 'corrects assignment to an if elsif else with multiple elsifs' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 1
               elsif foobar
                 2
@@ -636,7 +636,7 @@
     it 'corrects assignment to an unless else condition' do
       expect_offense(<<~RUBY)
         bar = unless foo
-        ^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
                 1
               else
                 2
@@ -655,7 +655,7 @@
     it 'corrects assignment to a case when else condition' do
       expect_offense(<<~RUBY)
         bar = case foo
-        ^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               when foobar
                 1
               else
@@ -676,7 +676,7 @@
     it 'corrects assignment to a case when else with multiple whens' do
       expect_offense(<<~RUBY)
         bar = case foo
-        ^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               when foobar
                 1
               when baz
@@ -701,7 +701,7 @@
     it 'corrects assignment to a ternary operator' do
       expect_offense(<<~RUBY)
         bar = foo? ? 1 : 2
-        ^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
       RUBY
 
       expect_correction(<<~RUBY)
@@ -793,7 +793,7 @@
     it 'registers an offense for assignment using a method that ends with an equal sign' do
       expect_offense(<<~RUBY)
         self.attributes = foo? ? 1 : 2
-        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
       RUBY
 
       expect_correction(<<~RUBY)
@@ -804,7 +804,7 @@
     it 'registers an offense for assignment using []=' do
       expect_offense(<<~RUBY)
         foo[:a] = if bar?
-        ^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
                     1
                   else
                     2
@@ -823,7 +823,7 @@
     it 'registers an offense for assignment to an if then else' do
       expect_offense(<<~RUBY)
         bar = if foo then 1
-        ^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               else 2
               end
       RUBY
@@ -838,7 +838,7 @@
     it 'registers an offense for an assignment that uses if branch bodies including a block' do
       expect_offense(<<~RUBY)
         result = if condition
-        ^^^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
           foo do
           end
         else
@@ -861,7 +861,7 @@
     it 'registers an offense for assignment to case when then else' do
       expect_offense(<<~RUBY)
         baz = case foo
-        ^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               when bar then 1
               else 2
               end
@@ -878,7 +878,7 @@
     it 'registers an offense when empty `case` condition' do
       expect_offense(<<~RUBY)
         var = case
-        ^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^ Assign variables inside of conditionals.
         when foo
           bar
         else
@@ -907,7 +907,7 @@
     it 'corrects assignment to a namespaced constant' do
       expect_offense(<<~RUBY)
         FOO::BAR = if baz?
-        ^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
                       1
                     else
                       2
@@ -926,7 +926,7 @@
     it 'corrects assignment when without `else` branch' do
       expect_offense(<<~RUBY)
         var = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
           bar
         elsif baz
           qux
@@ -1024,7 +1024,7 @@
     it 'corrects assignment to a multiline if else condition' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 something
                 1
               else
@@ -1047,7 +1047,7 @@
     it 'corrects assignment to a multiline if elsif else condition' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 something
                 1
               elsif foobar
@@ -1076,7 +1076,7 @@
     it 'corrects assignment to an if elsif else with multiple elsifs' do
       expect_offense(<<~RUBY)
         bar = if foo
-        ^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^ Assign variables inside of conditionals.
                 something
                 1
               elsif foobar
@@ -1111,7 +1111,7 @@
     it 'corrects assignment to an unless else condition' do
       expect_offense(<<~RUBY)
         bar = unless foo
-        ^^^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^^^ Assign variables inside of conditionals.
                 something
                 1
               else
@@ -1134,7 +1134,7 @@
     it 'corrects assignment to a case when else condition' do
       expect_offense(<<~RUBY)
         bar = case foo
-        ^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               when foobar
                 something
                 1
@@ -1159,7 +1159,7 @@
     it 'corrects assignment to a case when else with multiple whens' do
       expect_offense(<<~RUBY)
         bar = case foo
-        ^^^^^^^^^^^^^^ Assign variables inside of conditionals
+        ^^^^^^^^^^^^^^ Assign variables inside of conditionals.
               when foobar
                 something
                 1
diff --git a/spec/support/cops/alignment_directive.rb b/spec/support/cops/alignment_directive.rb
index 12d7b1d361a..64713d31cf3 100644
--- a/spec/support/cops/alignment_directive.rb
+++ b/spec/support/cops/alignment_directive.rb
@@ -10,7 +10,7 @@ module Test
       class AlignmentDirective < RuboCop::Cop::Base
         extend AutoCorrector
 
-        MSG = 'Indent this node'
+        MSG = 'Indent this node.'
 
         def on_new_investigation
           processed_source.ast_with_comments.each do |node, comments|