diff --git a/CHANGES.md b/CHANGES.md
index 16011d82..011ac71f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -41,6 +41,9 @@
   robotidy --check --overwrite src
   ```
 
+### Fixes
+- Unmodified files are now not saved to the disk ([#237](https://github.com/MarketSquare/robotframework-tidy/issues/237))
+
 ## 1.6.2
 
 ### Fixes
diff --git a/robotidy/app.py b/robotidy/app.py
index 2ed324cd..0cafda75 100644
--- a/robotidy/app.py
+++ b/robotidy/app.py
@@ -67,7 +67,7 @@ def transform_files(self):
                 self.output_diff(model.source, old_model, new_model)
                 if stdin:
                     self.print_to_stdout(new_model)
-                else:
+                elif diff:
                     self.save_model(model.source, model)
             except DataError:
                 click.echo(
diff --git a/tests/atest/transformers/AlignTestCases/expected/empty_line.robot b/tests/atest/transformers/AlignTestCases/expected/empty_line.robot
deleted file mode 100644
index d4c340b3..00000000
--- a/tests/atest/transformers/AlignTestCases/expected/empty_line.robot
+++ /dev/null
@@ -1,12 +0,0 @@
-*** Settings ***
-Test Template       bar
-
-*** Test Cases ***      baz         qux
-test1
-                        hi          hello
-test2 long test name
-                        asdfasdf    asdsdfgsdfg
-
-*** Keywords ***
-bar
-    [Arguments]    ${baz}    ${qux}
\ No newline at end of file
diff --git a/tests/atest/transformers/AlignTestCases/expected/for_loops.robot b/tests/atest/transformers/AlignTestCases/expected/for_loops.robot
deleted file mode 100644
index c9467798..00000000
--- a/tests/atest/transformers/AlignTestCases/expected/for_loops.robot
+++ /dev/null
@@ -1,22 +0,0 @@
-*** Test Cases ***    header1            header2
-My Test Case
-                      [Documentation]    This is a documentation
-                      ...                in two lines
-                      My TC Step 1       my step arg                   # step 1 comment
-                      My TC Step 2       my step \ 2 arg               second arg                   # step 2 comment
-                      ...                third arg split to own row
-                      ...                fourth and                    fifth as well                # comment
-                      [Teardown]         1 minute
-
-A very long named test case
-                      My step 1          This is arg
-                      My step 2          This also is arg
-                      ...                Split line                    Longest argument on split
-
-Test with for         FOR                ${i}                          IN RANGE                     100
-                                         Log                           ${i}
-                                         ${result} =                   My kw
-                                         Log Many                      1st
-                                         ...                           2nd
-                                         ...                           3rd
-                      END
\ No newline at end of file
diff --git a/tests/atest/transformers/AlignTestCases/expected/no_header_col_only_headers.robot b/tests/atest/transformers/AlignTestCases/expected/no_header_col_only_headers.robot
deleted file mode 100644
index f24b159c..00000000
--- a/tests/atest/transformers/AlignTestCases/expected/no_header_col_only_headers.robot
+++ /dev/null
@@ -1,13 +0,0 @@
-*** Settings ***
-Test Template       bar
-
-*** Test Cases ***
-# some comment
-test1    hi    hello
-test2 long test name    asdfasdf    asdsdfgsdfg
-    bar1  bar2
-# some comment
-
-*** Keywords ***
-bar
-    [Arguments]    ${baz}    ${qux}
diff --git a/tests/atest/transformers/AlignTestCases/test_transformer.py b/tests/atest/transformers/AlignTestCases/test_transformer.py
index 4f86fd59..7f4964b2 100644
--- a/tests/atest/transformers/AlignTestCases/test_transformer.py
+++ b/tests/atest/transformers/AlignTestCases/test_transformer.py
@@ -11,21 +11,23 @@ class TestAlignTestCases(TransformerAcceptanceTest):
         [
             "test.robot",
             "no_header_col.robot",
-            "for_loops.robot",
             "with_settings.robot",
             "templated_for_loops.robot",
             "templated_for_loops_and_without.robot",
             "templated_for_loops_header_cols.robot",
-            "empty_line.robot",
         ],
     )
     def test_transformer(self, source):
         self.compare(source=source, expected=source)
 
+    @pytest.mark.parametrize("source", ["for_loops.robot", "empty_line.robot"])
+    def test_should_not_modify(self, source):
+        self.compare(source=source, not_modified=True)
+
     def test_only_with_headers(self):
         self.compare(
             source="no_header_col.robot",
-            expected="no_header_col_only_headers.robot",
+            not_modified=True,
             config=":only_with_headers=True",
         )
 
diff --git a/tests/atest/transformers/InlineIf/expected/invalid_if.robot b/tests/atest/transformers/InlineIf/expected/invalid_if.robot
deleted file mode 100644
index 444484e3..00000000
--- a/tests/atest/transformers/InlineIf/expected/invalid_if.robot
+++ /dev/null
@@ -1,133 +0,0 @@
-*** Test Cases ***
-IF without condition
-    [Documentation]    FAIL    IF must have a condition.
-    IF
-        Fail    Should not be run
-    END
-
-IF without condition with ELSE
-    [Documentation]    FAIL    IF must have a condition.
-    IF
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    END
-
-IF without END
-    [Documentation]    FAIL    IF has no closing END.
-    IF    ${True}
-        Fail    Should not be run
-
-Invalid END
-    [Documentation]    FAIL    END does not accept arguments, got 'this', 'is' and 'invalid'.
-    IF    True
-        Fail    Should not be run
-    END    this    is    invalid
-
-IF with wrong case
-    [Documentation]    FAIL    'If' is a reserved keyword. It must be an upper case 'IF' when used as a marker.
-    if    ${True}
-        Fail    Should not be run
-    END
-
-ELSE IF without condition
-    [Documentation]    FAIL    ELSE IF must have a condition.
-    IF    'mars' == 'mars'
-        Fail    Should not be run
-    ELSE IF
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    END
-
-ELSE IF with multiple conditions
-    [Documentation]    FAIL    ELSE IF cannot have more than one condition.
-    IF    'maa' == 'maa'
-        Fail    Should not be run
-    ELSE IF    ${False}    ooops    ${True}
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    END
-
-ELSE with condition
-    [Documentation]    FAIL    ELSE does not accept arguments, got '\${True}'.
-    IF    'venus' != 'mars'
-        Fail    Should not be run
-    ELSE    ${True}
-        Fail    Should not be run
-    END
-
-IF with empty body
-    [Documentation]    FAIL    IF branch cannot be empty.
-    IF    'jupiter' == 'saturnus'
-    END
-
-ELSE with empty body
-    [Documentation]    FAIL    ELSE branch cannot be empty.
-    IF    'kuu' == 'maa'
-        Fail    Should not be run
-    ELSE
-    END
-
-ELSE IF with empty body
-    [Documentation]    FAIL    ELSE IF branch cannot be empty.
-    IF    'mars' == 'maa'
-        Fail    Should not be run
-    ELSE IF    ${False}
-    ELSE
-        Fail    Should not be run
-    END
-
-ELSE after ELSE
-    [Documentation]    FAIL    Multiple ELSE branches.
-    IF    'kuu' == 'maa'
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    END
-
-ELSE IF after ELSE
-    [Documentation]    FAIL    ELSE IF after ELSE.
-    IF    'kuu' == 'maa'
-        Fail    Should not be run
-    ELSE
-        Fail    Should not be run
-    ELSE IF    ${True}
-        Log    hei
-    END
-
-Invalid IF inside FOR
-    [Documentation]    FAIL    ELSE IF after ELSE.
-    FOR    ${value}    IN    1    2    3
-        IF    ${value} == 1
-            Fail    Should not be run
-        ELSE
-            Fail    Should not be run
-        ELSE IF    ${value} == 3
-            Fail    Should not be run
-        END
-    END
-
-Multiple errors
-    [Documentation]    FAIL
-    ...    Multiple errors:
-    ...    - IF must have a condition.
-    ...    - IF branch cannot be empty.
-    ...    - ELSE IF after ELSE.
-    ...    - Multiple ELSE branches.
-    ...    - IF has no closing END.
-    ...    - ELSE IF cannot have more than one condition.
-    ...    - ELSE IF branch cannot be empty.
-    ...    - ELSE does not accept arguments, got 'oops'.
-    ...    - ELSE branch cannot be empty.
-    ...    - ELSE IF must have a condition.
-    ...    - ELSE IF branch cannot be empty.
-    ...    - ELSE branch cannot be empty.
-    IF
-    ELSE IF    too    many
-    ELSE    oops
-    ELSE IF
-    ELSE
diff --git a/tests/atest/transformers/InlineIf/expected/invalid_inline_if.robot b/tests/atest/transformers/InlineIf/expected/invalid_inline_if.robot
deleted file mode 100644
index 6fdef4bd..00000000
--- a/tests/atest/transformers/InlineIf/expected/invalid_inline_if.robot
+++ /dev/null
@@ -1,160 +0,0 @@
-*** Test Cases ***
-Invalid condition
-    [Documentation]    FAIL Evaluating IF condition failed: Evaluating expression 'ooops' failed: NameError: name 'ooops' is not defined nor importable as module
-    IF    ooops    Not run    ELSE    Not run either
-
-Condition with non-existing variable
-    [Documentation]    FAIL Evaluating IF condition failed: Variable '\${ooops}' not found.
-    IF    ${ooops}    Not run
-
-Invalid condition with other error
-    [Documentation]    FAIL ELSE branch cannot be empty.
-    IF    bad    Not run    ELSE
-
-Empty IF
-    [Documentation]    FAIL Multiple errors:
-    ...    - IF must have a condition.
-    ...    - IF branch cannot be empty.
-    ...    - IF has no closing END.
-    IF
-
-IF without branch
-    [Documentation]    FAIL Multiple errors:
-    ...    - IF branch cannot be empty.
-    ...    - IF has no closing END.
-    IF    True
-
-IF without branch with ELSE IF
-    [Documentation]    FAIL IF branch cannot be empty.
-    IF    True    ELSE IF    True    Not run
-
-IF without branch with ELSE
-    [Documentation]    FAIL IF branch cannot be empty.
-    IF    True    ELSE    Not run
-
-IF followed by ELSE IF
-    [Documentation]    FAIL STARTS: Evaluating IF condition failed: Evaluating expression 'ELSE IF' failed:
-    IF    ELSE IF   False    Not run
-
-IF followed by ELSE
-    [Documentation]    FAIL Evaluating IF condition failed: Evaluating expression 'ELSE' failed: NameError: name 'ELSE' is not defined nor importable as module
-    IF    ELSE    Not run
-
-Empty ELSE IF 1
-    [Documentation]    FAIL Multiple errors:
-    ...    - ELSE IF must have a condition.
-    ...    - ELSE IF branch cannot be empty.
-    IF    False    Not run    ELSE IF
-
-Empty ELSE IF 2
-    [Documentation]    FAIL Evaluating ELSE IF condition failed: Evaluating expression 'ELSE' failed: NameError: name 'ELSE' is not defined nor importable as module
-    IF    False    Not run    ELSE IF    ELSE    Not run
-
-ELSE IF without branch 1
-    [Documentation]   FAIL ELSE IF branch cannot be empty.
-    IF    False    Not run    ELSE IF    False
-
-ELSE IF without branch 2
-    [Documentation]   FAIL ELSE IF branch cannot be empty.
-    IF    False    Not run    ELSE IF    False    ELSE    Not run
-
-Empty ELSE
-    [Documentation]    FAIL ELSE branch cannot be empty.
-    IF    True    Not run    ELSE IF    True    Not run    ELSE
-
-ELSE IF after ELSE 1
-    [Documentation]    FAIL ELSE IF after ELSE.
-    IF    True    Not run    ELSE    Not run    ELSE IF    True    Not run
-
-ELSE IF after ELSE 2
-    [Documentation]    FAIL ELSE IF after ELSE.
-    IF    True    Not run    ELSE    Not run    ELSE IF    True    Not run     ELSE IF    True    Not run
-
-Multiple ELSEs 1
-    [Documentation]    FAIL Multiple ELSE branches.
-    IF    True    Not run    ELSE    Not run    ELSE    Not run
-
-Multiple ELSEs 2
-    [Documentation]    FAIL Multiple ELSE branches.
-    IF    True    Not run    ELSE    Not run    ELSE    Not run    ELSE    Not run
-
-Nested IF 1
-    [Documentation]    FAIL Inline IF cannot be nested.
-    IF    True    IF    True    Not run
-
-Nested IF 2
-    [Documentation]    FAIL Inline IF cannot be nested.
-    IF    True    Not run    ELSE    IF    True    Not run
-
-Nested IF 3
-    [Documentation]    FAIL Inline IF cannot be nested.
-    IF                True    IF    True    Not run
-    ...    ELSE IF    True    IF    True    Not run
-    ...    ELSE               IF    True    Not run
-
-Nested FOR
-    [Documentation]    FAIL 'For' is a reserved keyword. It must be an upper case 'FOR' when used as a marker.
-    IF    True    FOR    ${x}    IN    @{stuff}
-
-Unnecessary END
-    [Documentation]    FAIL Keyword 'BuiltIn.No Operation' expected 0 arguments, got 1.
-    IF    True     No operation    ELSE    Log    END
-    IF    False    Not run         ELSE    No operation    END
-
-Invalid END after inline header
-    [Documentation]    FAIL 'End' is a reserved keyword. It must be an upper case 'END' when used as a marker to close a block.
-    IF    True    Log    Executed inside inline IF
-        Log   Executed outside IF
-    END
-
-Assign in IF branch
-    [Documentation]    FAIL Inline IF branches cannot contain assignments.
-    IF    False    ${x} =    Whatever
-
-Assign in ELSE IF branch
-    [Documentation]    FAIL Inline IF branches cannot contain assignments.
-    IF    False    Keyword    ELSE IF   False    ${x} =    Whatever
-
-Assign in ELSE branch
-    [Documentation]    FAIL Inline IF branches cannot contain assignments.
-    IF    False    Keyword    ELSE    ${x} =    Whatever
-
-Invalid assign mark usage
-    [Documentation]    FAIL Assign mark '=' can be used only with the last variable.
-    ${x} =    ${y}    IF    True    Create list    x    y
-
-Too many list variables in assign
-    [Documentation]    FAIL Assignment can contain only one list variable.
-    @{x}    @{y} =    IF    True    Create list    x    y    ELSE    Not run
-
-Invalid number of variables in assign
-    [Documentation]    FAIL Cannot set variables: Expected 2 return values, got 3.
-    ${x}    ${y} =    IF    False    Create list    x    y     ELSE    Create list    x    y    z
-
-Invalid value for list assign
-    [Documentation]    FAIL Cannot set variable '\@{x}': Expected list-like value, got string.
-    @{x} =    IF    True    Set variable    String is not list
-
-Invalid value for dict assign
-    [Documentation]    FAIL Cannot set variable '\&{x}': Expected dictionary-like value, got string.
-    &{x} =    IF    False    Not run    ELSE    Set variable    String is not dict either
-
-Assign when IF branch is empty
-    [Documentation]    FAIL IF branch cannot be empty.
-    ${x} =    IF    False
-
-Assign when ELSE IF branch is empty
-    [Documentation]    FAIL ELSE IF branch cannot be empty.
-    ${x} =    IF    True    Not run    ELSE IF    True
-
-Assign when ELSE branch is empty
-    [Documentation]    FAIL ELSE branch cannot be empty.
-    ${x} =    IF    True    Not run    ELSE
-
-Assign with RETURN
-    [Documentation]    FAIL Inline IF with assignment can only contain keyword calls.
-    Assign with RETURN
-
-*** Keywords ***
-Assign with RETURN
-    ${x} =    IF    False    RETURN    ELSE    Not run
diff --git a/tests/atest/transformers/InlineIf/test_transformer.py b/tests/atest/transformers/InlineIf/test_transformer.py
index 3fa9126c..241ba8f7 100644
--- a/tests/atest/transformers/InlineIf/test_transformer.py
+++ b/tests/atest/transformers/InlineIf/test_transformer.py
@@ -11,7 +11,7 @@ def test_transformer_skip_else(self):
         self.compare(source="test.robot", expected="test_skip_else.robot", config=":skip_else=True:line_length=120")
 
     def test_invalid_if(self):
-        self.compare(source="invalid_if.robot")
+        self.compare(source="invalid_if.robot", not_modified=True)
 
     def test_invalid_inline_if(self):
-        self.compare(source="invalid_inline_if.robot", config=":line_length=120")
+        self.compare(source="invalid_inline_if.robot", not_modified=True, config=":line_length=120")
diff --git a/tests/atest/transformers/MergeAndOrderSections/expected/order.robot b/tests/atest/transformers/MergeAndOrderSections/expected/order.robot
deleted file mode 100644
index e674caef..00000000
--- a/tests/atest/transformers/MergeAndOrderSections/expected/order.robot
+++ /dev/null
@@ -1,16 +0,0 @@
-*** Comments ***
-stuff
-
-*** Settings ***
-Library  stuff
-
-*** Variables ***
-${variable}  stuff
-
-*** Test Cases ***
-Test
-    Keyword
-
-*** Keywords ***
-Keyword
-    No Operation
diff --git a/tests/atest/transformers/MergeAndOrderSections/expected/parsing_error.robot b/tests/atest/transformers/MergeAndOrderSections/expected/parsing_error.robot
deleted file mode 100644
index b6b9d9b2..00000000
--- a/tests/atest/transformers/MergeAndOrderSections/expected/parsing_error.robot
+++ /dev/null
@@ -1,62 +0,0 @@
-*** Settings ***
-Documentation  doc
-
-
-*** Test Cases ***
-Test
-    [Documentation]  doc
-    [Tags]  sometag
-    Pass
-    Keyword
-    One More
-
-
-*** Keywords ***
-Keyword
-    [Documentation]  this is doc
-    [Argument]
-    No Operation
-    Pass
-    No Operation
-    Fail
-    IF    ${condition}
-        Keyword
-    End
-    IF    ${condition}
-        Keyword
-    ELSE IF  ${condition}    Empty Body
-    END
-    IF    ${condition}
-        Keyword
-    ELse IF   ${condition}
-        Keyword
-    END
-    IF    ${condition}
-        Keyword
-    ELSE IF   ${condition}
-        Keyword
-    ElSE
-        Keyword
-    END
-    IF    ${condition}    ${condition}
-        Keyword
-    END
-    IF    ${condition} ==
-    \   ${flag}
-        Keyword
-    END
-
-For Loop
-    FOR  IN RANGE  10
-        Keyword
-    END
-    FOR  ${var}  IN  @{list}
-    END
-    FOR  ${var}  IN RANGE
-        Keyword
-    END
-    FOR  ${var}  IN RANGE  10
-        Keyword
-    FOR  ${var}  @{list}
-        Keyword
-    END
\ No newline at end of file
diff --git a/tests/atest/transformers/MergeAndOrderSections/test_transformer.py b/tests/atest/transformers/MergeAndOrderSections/test_transformer.py
index 7736b807..67b02b16 100644
--- a/tests/atest/transformers/MergeAndOrderSections/test_transformer.py
+++ b/tests/atest/transformers/MergeAndOrderSections/test_transformer.py
@@ -25,13 +25,13 @@ def test_empty_section(self):
         self.compare(source="empty_section.robot")
 
     def test_parsing_error(self):
-        self.compare(source="parsing_error.robot")
+        self.compare(source="parsing_error.robot", not_modified=True)
 
     def test_too_few_calls_in_keyword(self):
         self.compare(source="too_few_calls_in_keyword.robot")
 
     def test_default_order(self):
-        self.compare(source="order.robot")
+        self.compare(source="order.robot", not_modified=True)
 
     def test_custom_order(self):
         self.compare(
diff --git a/tests/atest/transformers/NormalizeNewLines/test_transformer.py b/tests/atest/transformers/NormalizeNewLines/test_transformer.py
index e6c7787c..24116bd2 100644
--- a/tests/atest/transformers/NormalizeNewLines/test_transformer.py
+++ b/tests/atest/transformers/NormalizeNewLines/test_transformer.py
@@ -33,12 +33,11 @@ def test_templated_tests_separated(self):
             config=":separate_templated_tests=True",
         )
 
-    @pytest.mark.parametrize("lines_at_the_end", [0, 1])
-    def test_test_case_last(self, lines_at_the_end):
-        self.compare(
-            source=f"test_case_last_{lines_at_the_end}_lines.robot",
-            expected="test_case_last.robot",
-        )
+    def test_test_case_last_0(self):
+        self.compare(source=f"test_case_last_0_lines.robot", expected="test_case_last.robot")
+
+    def test_test_case_last_1(self):
+        self.compare(source=f"test_case_last_1_lines.robot", not_modified=True)
 
     @pytest.mark.parametrize("empty_lines", [0, 1, 2])
     def test_consecutive_empty_lines(self, empty_lines):
diff --git a/tests/atest/transformers/NormalizeSeparators/expected/empty_sections.robot b/tests/atest/transformers/NormalizeSeparators/expected/empty_sections.robot
deleted file mode 100644
index 7b2d47bb..00000000
--- a/tests/atest/transformers/NormalizeSeparators/expected/empty_sections.robot
+++ /dev/null
@@ -1,47 +0,0 @@
-  # this is   comment
-
-*** Settings ***
-Library  library.py  WITH NAME          alias
-
-Force Tags           tag
-...   tag
-
-Documentation  doc
-...      multi
-...  line
-
-*** Variables ***
-${var}     3
- ${var2}  4
-
-*** Test Cases ***
-Test case
-  [Setup]  Keyword
-   Keyword  with  arg
-   ...  and  multi  lines
-     [Teardown]          Keyword
-
-Test case with structures
-    FOR  ${variable}  IN  1  2
-    Keyword
-     IF  ${condition}
-       Log  ${stuff}  console=True
-  END
-   END
-
-*** Keywords ***
-Keyword
-Another Keyword
-          [Arguments]  ${arg}
-       Should Be Equal  1
-       ...  ${arg}
-   IF  ${condition}
-        FOR  ${v}  IN RANGE  10
-   Keyword
-        END
-   END
-
-Keyword With Tabulators
-    Keyword
-    ...  2
-	...  ${arg}
diff --git a/tests/atest/transformers/NormalizeSeparators/test_transformer.py b/tests/atest/transformers/NormalizeSeparators/test_transformer.py
index 2e282d51..2dfc8f8e 100644
--- a/tests/atest/transformers/NormalizeSeparators/test_transformer.py
+++ b/tests/atest/transformers/NormalizeSeparators/test_transformer.py
@@ -20,8 +20,12 @@ def test_pipes(self):
         ["", "comments,settings,variables", "comment,keywords", "comments,settings,variable,keywords,testcases"],
     )
     def test_disable_section(self, sections):
-        expected = "empty_sections.robot" if not sections else sections.replace(",", "_") + ".robot"
-        self.compare(source="test.robot", expected=expected, config=f":sections={sections}")
+        if sections:
+            self.compare(
+                source="test.robot", expected=sections.replace(",", "_") + ".robot", config=f":sections={sections}"
+            )
+        else:
+            self.compare(source="test.robot", not_modified=True, config=f":sections={sections}")
 
     def test_configure_invalid_section(self):
         result = self.run_tidy(
diff --git a/tests/atest/transformers/OrderSettingsSection/expected/just_comment.robot b/tests/atest/transformers/OrderSettingsSection/expected/just_comment.robot
deleted file mode 100644
index a22c71d5..00000000
--- a/tests/atest/transformers/OrderSettingsSection/expected/just_comment.robot
+++ /dev/null
@@ -1,2 +0,0 @@
-*** Settings ***
-# comment
diff --git a/tests/atest/transformers/OrderSettingsSection/test_transformer.py b/tests/atest/transformers/OrderSettingsSection/test_transformer.py
index 51483fb0..6781b12a 100644
--- a/tests/atest/transformers/OrderSettingsSection/test_transformer.py
+++ b/tests/atest/transformers/OrderSettingsSection/test_transformer.py
@@ -13,7 +13,7 @@ def test_missing_group(self):
         self.compare(source="missing_group.robot")
 
     def test_just_comment(self):
-        self.compare(source="just_comment.robot")
+        self.compare(source="just_comment.robot", not_modified=True)
 
     def test_last_section(self):
         self.compare(source="last_section.robot")
diff --git a/tests/atest/transformers/RenameTestCases/expected/empty_test_name.robot b/tests/atest/transformers/RenameTestCases/expected/empty_test_name.robot
deleted file mode 100644
index f1e99d3d..00000000
--- a/tests/atest/transformers/RenameTestCases/expected/empty_test_name.robot
+++ /dev/null
@@ -1,11 +0,0 @@
-*** Test Cases ***
-
-#  no test case name!!!
-    Log To Console  hello
-
-Proper test
-    [documentation]  doc
-    [tags]  sometag
-    Pass
-    Keyword
-    One More
diff --git a/tests/atest/transformers/RenameTestCases/test_transformer.py b/tests/atest/transformers/RenameTestCases/test_transformer.py
index 481936d3..9e60cb94 100644
--- a/tests/atest/transformers/RenameTestCases/test_transformer.py
+++ b/tests/atest/transformers/RenameTestCases/test_transformer.py
@@ -8,7 +8,7 @@ def test_transformer(self):
         self.compare(source="test.robot", expected="test.robot")
 
     def test_test_without_name(self):
-        self.compare(source="empty_test_name.robot", expected="empty_test_name.robot")
+        self.compare(source="empty_test_name.robot", not_modified=True)
 
     def test_replace_pattern_to_empty(self):
         self.compare(
diff --git a/tests/atest/transformers/ReplaceBreakContinue/expected/errors.robot b/tests/atest/transformers/ReplaceBreakContinue/expected/errors.robot
deleted file mode 100644
index e8563d4a..00000000
--- a/tests/atest/transformers/ReplaceBreakContinue/expected/errors.robot
+++ /dev/null
@@ -1,13 +0,0 @@
-*** Test Cases ***
-Missing condition
-    FOR    ${var}  IN RANGE  2
-        Continue For Loop If
-        Exit For Loop If
-    END
-
-*** Keywords ***
-Missing condition
-    FOR    ${var}  IN RANGE  2
-        Continue For Loop If
-        Exit For Loop If
-    END
diff --git a/tests/atest/transformers/ReplaceBreakContinue/test_transformer.py b/tests/atest/transformers/ReplaceBreakContinue/test_transformer.py
index 198f9bd5..b93ce682 100644
--- a/tests/atest/transformers/ReplaceBreakContinue/test_transformer.py
+++ b/tests/atest/transformers/ReplaceBreakContinue/test_transformer.py
@@ -1,11 +1,11 @@
-import pytest
-
 from .. import TransformerAcceptanceTest
 
 
 class TestReplaceBreakContinue(TransformerAcceptanceTest):
     TRANSFORMER_NAME = "ReplaceBreakContinue"
 
-    @pytest.mark.parametrize("source", ["test.robot", "errors.robot"])
-    def test_transformer(self, source):
-        self.compare(source=source)
+    def test_transformer(self):
+        self.compare(source="test.robot")
+
+    def test_with_errors(self):
+        self.compare(source="errors.robot", not_modified=True)
diff --git a/tests/atest/transformers/ReplaceReturns/expected/errors.robot b/tests/atest/transformers/ReplaceReturns/expected/errors.robot
deleted file mode 100644
index 916b81f7..00000000
--- a/tests/atest/transformers/ReplaceReturns/expected/errors.robot
+++ /dev/null
@@ -1,9 +0,0 @@
-*** Test Cases ***
-Return From Keyword
-    Return From Keyword If
-    Run Keyword And Return If  $condition
-
-*** Keywords ***
-Return From Keyword
-    Return From Keyword If
-    Run Keyword And Return If  $condition
diff --git a/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return.robot b/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return.robot
deleted file mode 100644
index 121f4a1b..00000000
--- a/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return.robot
+++ /dev/null
@@ -1,12 +0,0 @@
-*** Test Cases ***
-For and Ifs
-    FOR    ${var}  IN  1  2
-        IF    $var == 2
-            Run Keyword And Return    Keyword   ${arg}
-        END
-    END
-
-*** Keywords ***
-Testing
-    Run Keyword And Return    Keyword   ${arg}
-    ...  ${arg2}
diff --git a/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return_if.robot b/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return_if.robot
deleted file mode 100644
index f8382391..00000000
--- a/tests/atest/transformers/ReplaceReturns/expected/run_keyword_and_return_if.robot
+++ /dev/null
@@ -1,14 +0,0 @@
-*** Keywords ***
-First
-    ${var}    Set Variable    1
-    FOR    ${variable}  IN  1  2
-        Run Keyword And Return If    ${var}==2  Keyword 2    ${var}
-        Log    ${variable}
-    END
-
-With IF
-    ${var}    Set Variable    1
-    IF    ${var}>0
-        Run Keyword And Return If    $var    Some Keyword    ${var}
-          ...  1
-    END
diff --git a/tests/atest/transformers/ReplaceReturns/test_transformer.py b/tests/atest/transformers/ReplaceReturns/test_transformer.py
index fe7bf921..f1f1dafa 100644
--- a/tests/atest/transformers/ReplaceReturns/test_transformer.py
+++ b/tests/atest/transformers/ReplaceReturns/test_transformer.py
@@ -9,17 +9,25 @@ class TestReplaceReturns(TransformerAcceptanceTest):
     @pytest.mark.parametrize(
         "source",
         [
-            "errors.robot",
             "return_from_keyword.robot",
             "return_from_keyword_if.robot",
-            "run_keyword_and_return.robot",
-            "run_keyword_and_return_if.robot",
             "test.robot",
         ],
     )
     def test_transformer(self, source):
         self.compare(source=source)
 
+    @pytest.mark.parametrize(
+        "source",
+        [
+            "errors.robot",
+            "run_keyword_and_return.robot",
+            "run_keyword_and_return_if.robot",
+        ],
+    )
+    def test_should_not_modify(self, source):
+        self.compare(source=source, not_modified=True)
+
     def test_return_selected(self):
         self.compare(
             source="test.robot",
diff --git a/tests/atest/transformers/ReplaceRunKeywordIf/expected/golden.robot b/tests/atest/transformers/ReplaceRunKeywordIf/expected/golden.robot
deleted file mode 100644
index d0c589a5..00000000
--- a/tests/atest/transformers/ReplaceRunKeywordIf/expected/golden.robot
+++ /dev/null
@@ -1,121 +0,0 @@
-*** Test Cases ***
-Leave existing if blocks
-    IF    condition
-        Keyword
-    ELSE IF  condition2
-        Keyword2
-    ELSE
-        Keyword
-    END
-
-Single Return Value
-    IF    ${condition}
-        ${var}    Keyword With ${var}    ${arg}
-    END
-
-Multiple Return Values
-    IF    ${condition}
-        ${var}    ${var2}    Keyword With ${var}    ${arg}
-    END
-
-Run keyword if with else if
-    IF    ${condition}
-        Keyword
-    ELSE IF    ${other_condition}
-        Other Keyword
-    ELSE
-        Final Keyword
-    END
-
-Run keyword if with else if and args
-    IF    ${condition}
-        Keyword    a    b    c
-    ELSE IF    ${other_condition}
-        Other Keyword
-    ELSE
-        Final Keyword    1    2    ${var}
-    END
-
-Run keyword if with else if and return values
-    IF    ${condition}
-        ${var}    ${var}    Keyword
-    ELSE IF    ${other_condition}
-        ${var}    ${var}    Other Keyword    ${arg}
-    ELSE
-        ${var}    ${var}    Final Keyword
-    END
-
-Run keyword if with else if and run keywords
-    IF    "${var}"=="a"
-        First Keyword
-        Second Keyword    1    2
-    ELSE IF    ${var}==1
-        Single Keyword    ${argument}
-    ELSE
-        Normal Keyword    abc
-    END
-
-Run keyword if inside FOR loop
-    FOR  ${var}  IN  @{elems}
-        IF    ${condition}
-            Keyword
-        ELSE IF    ${other_condition}
-            Other Keyword
-        ELSE
-            Final Keyword
-        END
-    END
-
-Run keyword if inside IF
-    IF  ${condition}
-        IF    ${condition}
-            Keyword
-        ELSE IF    ${other_condition}
-            Other Keyword
-        ELSE
-            Final Keyword
-        END
-    END
-
-*** Keywords ***
-Test Content Merged Into One Keyword
-    IF    condition
-        Keyword
-    ELSE IF  condition2
-        Keyword2
-    ELSE
-        Keyword
-    END
-
-    IF    ${condition}
-        Keyword
-    ELSE IF    ${other_condition}
-        Other Keyword
-    ELSE
-        Final Keyword
-    END
-
-    IF    ${condition}
-        Keyword    a    b    c
-    ELSE IF    ${other_condition}
-        Other Keyword
-    ELSE
-        Final Keyword    1    2    ${var}
-    END
-
-    IF    ${condition}
-        ${var}    ${var}    Keyword
-    ELSE IF    ${other_condition}
-        ${var}    ${var}    Other Keyword    ${arg}
-    ELSE
-        ${var}    ${var}    Final Keyword
-    END
-
-    IF    "${var}"=="a"
-        First Keyword
-        Second Keyword    1    2
-    ELSE IF    ${var}==1
-        Single Keyword    ${argument}
-    ELSE
-        Normal Keyword    abc
-    END
diff --git a/tests/atest/transformers/ReplaceRunKeywordIf/test_transformer.py b/tests/atest/transformers/ReplaceRunKeywordIf/test_transformer.py
index b00e43d3..bb2e99d1 100644
--- a/tests/atest/transformers/ReplaceRunKeywordIf/test_transformer.py
+++ b/tests/atest/transformers/ReplaceRunKeywordIf/test_transformer.py
@@ -18,7 +18,7 @@ def test_invalid_data(self):
         self.compare(source="invalid_data.robot")
 
     def test_golden_file(self):
-        self.compare(source="golden.robot")
+        self.compare(source="golden.robot", not_modified=True)
 
     def test_remove_useless_set_variable(self):
         self.compare(source="set_variable_workaround.robot")
diff --git a/tests/atest/transformers/SmartSortKeywords/expected/empty_before_fist_keyword.robot b/tests/atest/transformers/SmartSortKeywords/expected/empty_before_fist_keyword.robot
deleted file mode 100644
index a081fb21..00000000
--- a/tests/atest/transformers/SmartSortKeywords/expected/empty_before_fist_keyword.robot
+++ /dev/null
@@ -1,4 +0,0 @@
-*** Keywords ***
-
-# My Comment
-my_kw
\ No newline at end of file
diff --git a/tests/atest/transformers/SmartSortKeywords/test_transformer.py b/tests/atest/transformers/SmartSortKeywords/test_transformer.py
index 2d771742..3acea6b5 100644
--- a/tests/atest/transformers/SmartSortKeywords/test_transformer.py
+++ b/tests/atest/transformers/SmartSortKeywords/test_transformer.py
@@ -57,7 +57,7 @@ def test_(self):
         )
 
     def test_empty_section(self):
-        self.compare(source="empty_before_fist_keyword.robot")
+        self.compare(source="empty_before_fist_keyword.robot", not_modified=True)
 
     def test_multiple_sections(self):
         self.compare(source="multiple_sections.robot")
diff --git a/tests/atest/transformers/__init__.py b/tests/atest/transformers/__init__.py
index ef60c60e..aaf91bb6 100644
--- a/tests/atest/transformers/__init__.py
+++ b/tests/atest/transformers/__init__.py
@@ -36,19 +36,33 @@ class TransformerAcceptanceTest:
     TRANSFORMER_NAME: str = "DUMMY"
 
     def compare(
-        self, source: str, expected: Optional[str] = None, config: str = "", target_version: Optional[int] = None
+        self,
+        source: str,
+        not_modified: bool = False,
+        expected: Optional[str] = None,
+        config: str = "",
+        target_version: Optional[int] = None,
     ):
+        """
+        Compare actual (source) and expected files. If expected filename is not provided it's assumed to be the same
+        as source.
+
+        Use not_modified flag if the content of the file shouldn't be modified by transformer.
+        """
         if not self.enabled_in_version(target_version):
             pytest.skip(f"Test enabled only for RF {target_version}.0")
         if expected is None:
             expected = source
         self.run_tidy(args=f"--transform {self.TRANSFORMER_NAME}{config}".split(), source=source)
-        self.compare_file(source, expected)
+        if not not_modified:
+            self.compare_file(source, expected)
 
-    def run_tidy(self, args: List[str] = None, source: str = None, exit_code: int = 0):
+    def run_tidy(self, args: List[str] = None, source: str = None, exit_code: int = 0, not_modified: bool = False):
         runner = CliRunner()
         output_path = str(Path(Path(__file__).parent, "actual", source))
         arguments = ["--output", output_path]
+        if not_modified:
+            arguments.append("--check")
         if args is not None:
             arguments += args
         if source is None:
diff --git a/tests/utest/test_cli.py b/tests/utest/test_cli.py
index 89d725d4..9fb0eb38 100644
--- a/tests/utest/test_cli.py
+++ b/tests/utest/test_cli.py
@@ -318,7 +318,10 @@ def test_check_overwrite(self, source, return_status, test_data_dir):
                 ["--check", "--overwrite", "--transform", "NormalizeSectionHeaderName", str(source)],
                 exit_code=return_status,
             )
-            mock_writer.assert_called()
+            if return_status:
+                mock_writer.assert_called()
+            else:
+                mock_writer.assert_not_called()
 
     def test_diff(self, test_data_dir):
         source = test_data_dir / "check" / "not_golden.robot"