Add option to align new lines to previous line in SplitTooLongLine transformer (#495)

* Add option to align new lines to previous line in SplitTooLongLine transformer

Co-authored-by: Mateusz Nojek <matnojek@gmail.com>

Author: bhirsz

docs/releasenotes/4.0.0.rst

@@ -226,6 +226,40 @@ this using ``split_single_value`` parameter (default ``False``)::
 
     > robotidy -c SplitTooLongLine:split_single_value=True
 
+SplitTooLongLine and aligning new line (#484)
+------------------------------------------------
+
+It is now possible to align new line to previous line when splitting too long line. This mode works only when we are
+filling the line until the line length limit (with one of the ``split_on_every_arg``, ``split_on_every_value`` and
+``split_on_every_setting_arg`` flags). To enable it configure it using ``align_new_line``::
+
+    > robotidy -c SplitTooLongLine:align_new_line=True
+
+Following code::
+
+    *** Keywords ***
+    Keyword
+        [Tags]    longertagname1    longertagname2    longertagname3
+        Keyword With Longer Name    ${arg1}    ${arg2}    ${arg3}    # let's assume ${arg3} does not fit under limit
+
+with  ``align_new_line = False`` (default) is transformed to::
+
+    *** Keywords ***
+    Keyword
+        [Tags]    longertagname1    longertagname2
+        ...    longertagname3
+        Keyword With Longer Name    ${arg1}    ${arg2}
+        ...    ${arg3}
+
+and with ``align_new_line = True`` is transformed to::
+
+    *** Keywords ***
+    Keyword
+        [Tags]    longertagname1    longertagname2
+        ...       longertagname3
+        Keyword With Longer Name    ${arg1}    ${arg2}
+        ...                         ${arg3}
+
 Spaces in the transformer name or configuration
 -------------------------------------------------
 
@@ -234,3 +268,8 @@ enclose it with quotation marks::
 
     > robotidy --load-transformer "C:\\My Transformers\\Transformer.py"
     > robotidy --configure CustomTransformer:value="param value"
+
+Bugs
+-----
+
+- Fixed the bug where keyword name would be prefixed with continuation marks (``...``) if name was longer than line length limit (#494)

docs/source/transformers/SplitTooLongLine.rst

@@ -229,6 +229,48 @@ to split on single too long values using ``split_single_value`` option::
             ${SINGLE_HEADER}
             ...    veeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeery
 
+Align new line
+----------------
+
+It is possible to align new line to previous line when splitting too long line. This mode works only when we are
+filling the line until line the length limit (with one of the ``split_on_every_arg``, ``split_on_every_value`` and
+``split_on_every_setting_arg`` flags). To enable it configure it using ``align_new_line``::
+
+    > robotidy -c SplitTooLongLine:align_new_line=True
+
+.. tab-set::
+
+    .. tab-item:: Before
+
+        .. code:: robotframework
+
+        *** Keywords ***
+        Keyword
+            [Tags]    longertagname1    longertagname2    longertagname3
+            Keyword With Longer Name    ${arg1}    ${arg2}    ${arg3}    # let's assume ${arg3} does not fit under limit
+
+    .. tab-item:: After (align_new_line = False)
+
+        .. code:: robotframework
+
+    *** Keywords ***
+    Keyword
+        [Tags]    longertagname1    longertagname2
+        ...    longertagname3
+        Keyword With Longer Name    ${arg1}    ${arg2}
+        ...    ${arg3}
+
+    .. tab-item:: After (align_new_line = True)
+
+        .. code:: robotframework
+
+    *** Keywords ***
+    Keyword
+        [Tags]    longertagname1    longertagname2
+        ...       longertagname3
+        Keyword With Longer Name    ${arg1}    ${arg2}
+        ...                         ${arg3}
+
 Ignore comments
 ----------------
 

robotidy/transformers/SplitTooLongLine.py

@@ -1,4 +1,5 @@
 import re
+from typing import List
 
 from robot.api.parsing import Comment, Token
 
@@ -83,6 +84,7 @@ def __init__(
         split_on_every_value: bool = True,
         split_on_every_setting_arg: bool = True,
         split_single_value: bool = False,
+        align_new_line: bool = False,
         skip: Skip = None,
     ):
         super().__init__(skip)
@@ -91,6 +93,7 @@ def __init__(
         self.split_on_every_value = split_on_every_value
         self.split_on_every_setting_arg = split_on_every_setting_arg
         self.split_single_value = split_single_value
+        self.align_new_line = align_new_line
         self.robocop_disabler_pattern = re.compile(
             r"(# )+(noqa|robocop: ?(?P<disabler>disable|enable)=?(?P<rules>[\w\-,]*))"
         )
@@ -228,7 +231,11 @@ def split_to_multiple_lines(tokens, indent, separator):
 
     def split_tokens(self, tokens, line, split_on, indent=None):
         separator = Token(Token.SEPARATOR, self.formatting_config.separator)
-        cont_indent = Token(Token.SEPARATOR, self.formatting_config.continuation_indent)
+        align_new_line = self.align_new_line and not split_on
+        if align_new_line:
+            cont_indent = None
+        else:
+            cont_indent = Token(Token.SEPARATOR, self.formatting_config.continuation_indent)
         split_tokens, comments = [], []
         # Comments with separators inside them are split into
         # [COMMENT, SEPARATOR, COMMENT] tokens in the AST, so in order to preserve the
@@ -240,20 +247,13 @@ def split_tokens(self, tokens, line, split_on, indent=None):
             if token.type == Token.SEPARATOR:
                 last_separator = token
             elif token.type == Token.COMMENT:
-                # AST splits comments with separators, e.g.
-                #
-                # "# Comment     rest" -> ["# Comment", "     ", "rest"].
-                #
-                # Notice the third value not starting with a hash - that's what this
-                # condition is about:
-                if comments and not token.value.startswith("#"):
-                    comments[-1].value += last_separator.value + token.value
-                else:
-                    comments.append(token)
+                self.join_split_comments(comments, token, last_separator)
             elif token.type == Token.ARGUMENT:
                 if token.value == "":
                     token.value = "${EMPTY}"
                 if split_on or not self.col_fit_in_line(line + [separator, token]):
+                    if align_new_line and cont_indent is None:  # we are yet to calculate aligned indent
+                        cont_indent = Token(Token.SEPARATOR, self.calculate_align_separator(line))
                     line.append(EOL)
                     split_tokens.extend(line)
                     if indent:
@@ -266,6 +266,28 @@ def split_tokens(self, tokens, line, split_on, indent=None):
         split_tokens.append(EOL)
         return split_tokens, comments
 
+    @staticmethod
+    def join_split_comments(comments: List, token: Token, last_separator: Token):
+        """Join split comments when splitting line.
+        AST splits comments with separators, e.g.
+        "# Comment     rest" -> ["# Comment", "     ", "rest"].
+        Notice the third value not starting with a hash - we need to join such comment with previous comment.
+        """
+        if comments and not token.value.startswith("#"):
+            comments[-1].value += last_separator.value + token.value
+        else:
+            comments.append(token)
+
+    def calculate_align_separator(self, line: List) -> str:
+        """Calculate width of the separator required to align new line to previous line."""
+        if len(line) <= 2:
+            # line only fits one column, so we don't have anything to align it for
+            return self.formatting_config.continuation_indent
+        first_data_token = next((token.value for token in line if token.type != Token.SEPARATOR), "")
+        # Decrease by 3 for ... token
+        align_width = len(first_data_token) + len(self.formatting_config.separator) - 3
+        return align_width * " "
+
     def split_variable_def(self, node):
         if len(node.value) < 2 and not self.split_single_value:
             return node
@@ -282,10 +304,11 @@ def split_keyword_call(self, node):
 
         keyword = node.get_token(Token.KEYWORD)
         # check if assign tokens needs to be split too
-        line = [indent, *self.join_on_separator(node.get_tokens(Token.ASSIGN), separator), keyword]
-        if not self.col_fit_in_line(line):
+        assign = node.get_tokens(Token.ASSIGN)
+        line = [indent, *self.join_on_separator(assign, separator), keyword]
+        if assign and not self.col_fit_in_line(line):
             head = [
-                *self.split_to_multiple_lines(node.get_tokens(Token.ASSIGN), indent=indent, separator=cont_indent),
+                *self.split_to_multiple_lines(assign, indent=indent, separator=cont_indent),
                 indent,
                 CONTINUATION,
                 cont_indent,
@@ -294,7 +317,6 @@ def split_keyword_call(self, node):
             line = []
         else:
             head = []
-
         tokens, comments = self.split_tokens(
             node.tokens[node.tokens.index(keyword) + 1 :], line, self.split_on_every_arg, indent
         )

tests/atest/transformers/SplitTooLongLine/expected/align_new_line.robot

@@ -0,0 +1,31 @@
+*** Settings ***
+Force Tags    PS_CSMON_15838    PR_PPD    PR_B450
+...           PR_B650    PR_B850    PR_CS1000
+...           PR_CS1000L    PAR_ECG    PAR_IP_1
+...           PAR_SPO2
+
+
+*** Variables ***  # variables are not aligned but it will be handled by AlignVariablesSection
+@{LIST}
+...    valuevaluevaluevaluevalue
+...    valuevaluevaluevaluevalue
+...    valuevaluevaluevaluevalue
+
+
+*** Test Cases ***
+Testcase with a lot of tags
+    [Tags]    Tag1    Tag10    Tag11    Tag12
+    ...       Tag13    Tag2    Tag3    Tag4
+    ...       Tag5    Tag6    Tag7    Tag8    Tag9
+    ...       Tag14    Tag15
+    Fail
+
+
+*** Keywords ***
+Keyword
+    Keyword With Longer Name    ${arg1}    ${arg2}
+    ...                         ${arg3}
+
+Keyword Longer Than Limit
+    This Keyword Goes Beyond Limit And Next Argument Should Be In New Line
+    ...    ${arg}

tests/atest/transformers/SplitTooLongLine/source/align_new_line.robot

@@ -0,0 +1,20 @@
+*** Settings ***
+Force Tags    PS_CSMON_15838    PR_PPD    PR_B450    PR_B650    PR_B850    PR_CS1000    PR_CS1000L    PAR_ECG    PAR_IP_1    PAR_SPO2
+
+
+*** Variables ***  # variables are not aligned but it will be handled by AlignVariablesSection
+@{LIST}    valuevaluevaluevaluevalue    valuevaluevaluevaluevalue    valuevaluevaluevaluevalue
+
+
+*** Test Cases ***
+Testcase with a lot of tags
+    [Tags]    Tag1    Tag10    Tag11    Tag12    Tag13    Tag2    Tag3    Tag4    Tag5    Tag6    Tag7    Tag8    Tag9    Tag14    Tag15
+    Fail
+
+
+*** Keywords ***
+Keyword
+    Keyword With Longer Name    ${arg1}    ${arg2}    ${arg3}
+
+Keyword Longer Than Limit
+    This Keyword Goes Beyond Limit And Next Argument Should Be In New Line    ${arg}

tests/atest/transformers/SplitTooLongLine/test_transformer.py

@@ -131,7 +131,6 @@ def test_split_settings_feed_until_line_length_skip_comments(self):
             config=":split_on_every_setting_arg=False:skip_comments=True",
         )
 
-
     @pytest.mark.parametrize(
         "skip_config",
         [
@@ -155,3 +154,9 @@ def test_split_on_single_value(self):
             expected="variables_split_scalar.robot",
             config=":split_single_value=True:line_length=80",
         )
+
+    def test_align_new_lines(self):
+        self.compare(
+            source="align_new_line.robot",
+            config=":align_new_line=True:split_on_every_arg=False:split_on_every_setting_arg=False:line_length=51",
+        )