Flash Tip — Automate Linting your .NET Solutions using Git Pre-Commit Hooks

By Charlie Dalldorf on January 25, 2024

Writing code is hard. Keeping your code styled consistently is harder. Nothing makes a developer question their sobriety more when their final project looks like it was written by ten different people, and you are the only author.

With this Hook, that will never happen ever again.

What You Need:

.editorconfig
Git
A Repository with a .NET Solution to format

EditorConfig helps maintain consistent coding styles for multiple developers working on the same project across various editors and IDEs.

Taken from https://editorconfig.org/

Initial Setup

First, we want to create a .NET Project Solution. Any of them are good, but I'm going to pick Web API. Next, we want to open up Powershell and execute git init in the root folder of our new solution. After that, we want to grab this .editorconfig file from CommunityToolkit's GitHub and place it in the same location as your solution file. This will give you a good jumping-off point for the .editorconfig file.

# Remove the line below if you want to inherit .editorconfig settings from higher directories
root = true

# All files
[*]

#### Core EditorConfig Options ####

# Encoding
charset = utf-8

# Indentation and spacing
tab_width = 4
indent_size = 4
indent_style = space

# New line preferences
end_of_line = unset
insert_final_newline = false

#### Build files ####

# Solution files
[*.{sln,slnx}]
tab_width = 4
indent_size = 4
indent_style = tab

# Configuration files
[*.{json,xml,yml,config,runsettings}]
indent_size = 2

# MSBuild files
[*.{slnf,props,targets,projitems,csproj,shproj}]
indent_size = 2

#### Source files ####

# Markdown files
[*.md]
indent_size = 2
insert_final_newline = true

# C# files
[*.cs]

#### File Header Template ####
file_header_template = Licensed to the .NET Foundation under one or more agreements.\nThe .NET Foundation licenses this file to you under the MIT license.\nSee the LICENSE file in the project root for more information.

#### .NET Coding Conventions ####

# this. and Me. preferences
dotnet_style_qualification_for_event = false:warning
dotnet_style_qualification_for_field = true:warning
dotnet_style_qualification_for_method = false:warning
dotnet_style_qualification_for_property = false:warning

# Language keywords vs BCL types preferences
dotnet_style_predefined_type_for_locals_parameters_members = true:warning
dotnet_style_predefined_type_for_member_access = true:warning

# Parentheses preferences
dotnet_style_parentheses_in_arithmetic_binary_operators = always_for_clarity:silent
dotnet_style_parentheses_in_other_binary_operators = always_for_clarity:silent
dotnet_style_parentheses_in_other_operators = never_if_unnecessary:silent
dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity:silent

# Modifier preferences (set to silent until https://github.com/dotnet/roslyn/issues/52904 is resolved)
dotnet_style_require_accessibility_modifiers = for_non_interface_members:silent

# Code block preferences
dotnet_style_allow_multiple_blank_lines_experimental = false:warning
dotnet_style_allow_statement_immediately_after_block_experimental = false:warning

# Expression-level preferences
csharp_style_deconstructed_variable_declaration = true:suggestion
csharp_style_inlined_variable_declaration = true:silent
csharp_style_throw_expression = true:suggestion
dotnet_style_coalesce_expression = true:suggestion
dotnet_style_collection_initializer = true:suggestion
dotnet_style_explicit_tuple_names = true:suggestion
dotnet_style_null_propagation = true:suggestion
dotnet_style_object_initializer = true:suggestion
dotnet_style_prefer_auto_properties = true:silent
dotnet_style_prefer_conditional_expression_over_assignment = true:silent
dotnet_style_prefer_conditional_expression_over_return = true:silent
dotnet_style_prefer_inferred_anonymous_type_member_names = true:suggestion
dotnet_style_prefer_inferred_tuple_names = true:suggestion
dotnet_style_prefer_is_null_check_over_reference_equality_method = true:warning

# Field preferences
dotnet_style_readonly_field = true:warning

#### C# Coding Conventions ####

# var preferences
csharp_style_var_elsewhere = false:warning
csharp_style_var_for_built_in_types = false:warning
csharp_style_var_when_type_is_apparent = false:warning

# Expression-bodied members
csharp_style_expression_bodied_accessors = false:silent
csharp_style_expression_bodied_constructors = false:silent
csharp_style_expression_bodied_indexers = false:silent
csharp_style_expression_bodied_lambdas = true:silent
csharp_style_expression_bodied_methods = false:silent
csharp_style_expression_bodied_operators = false:silent
csharp_style_expression_bodied_properties = false:silent

# Pattern matching preferences
csharp_style_prefer_pattern_matching = true:suggestion
csharp_style_pattern_matching_over_as_with_null_check = true:suggestion
csharp_style_pattern_matching_over_is_with_cast_check = true:suggestion

# Null-checking preferences
csharp_style_conditional_delegate_call = true:suggestion

# Modifier preferences
csharp_preferred_modifier_order = public,private,protected,internal,static,extern,new,virtual,abstract,sealed,override,readonly,unsafe,volatile,async

# Code-block preferences
csharp_prefer_braces = true:suggestion
csharp_using_directive_placement = outside_namespace:warning
csharp_style_namespace_declarations = file_scoped:warning
csharp_style_unused_value_assignment_preference = discard_variable:warning
csharp_style_unused_value_expression_statement_preference = discard_variable:warning
csharp_style_allow_blank_lines_between_consecutive_braces_experimental = false:warning

# Expression-level preferences
csharp_prefer_simple_default_expression = true:suggestion
csharp_prefer_static_local_function = true:warning
csharp_style_pattern_local_over_anonymous_function = true:warning

#### C# Formatting Rules ####

# New line preferences
csharp_new_line_before_catch = true
csharp_new_line_before_else = true
csharp_new_line_before_finally = true
csharp_new_line_before_members_in_anonymous_types = true
csharp_new_line_before_members_in_object_initializers = true
csharp_new_line_before_open_brace = all
csharp_new_line_between_query_expression_clauses = true

# Indentation preferences
csharp_indent_block_contents = true
csharp_indent_braces = false
csharp_indent_case_contents = true
csharp_indent_case_contents_when_block = false
csharp_indent_labels = no_change
csharp_indent_switch_labels = true

# Space preferences
csharp_space_after_cast = false
csharp_space_after_colon_in_inheritance_clause = true
csharp_space_after_comma = true
csharp_space_after_dot = false
csharp_space_after_keywords_in_control_flow_statements = true
csharp_space_after_semicolon_in_for_statement = true
csharp_space_around_binary_operators = before_and_after
csharp_space_around_declaration_statements = false
csharp_space_before_colon_in_inheritance_clause = true
csharp_space_before_comma = false
csharp_space_before_dot = false
csharp_space_before_open_square_brackets = false
csharp_space_before_semicolon_in_for_statement = false
csharp_space_between_empty_square_brackets = false
csharp_space_between_method_call_empty_parameter_list_parentheses = false
csharp_space_between_method_call_name_and_opening_parenthesis = false
csharp_space_between_method_call_parameter_list_parentheses = false
csharp_space_between_method_declaration_empty_parameter_list_parentheses = false
csharp_space_between_method_declaration_name_and_open_parenthesis = false
csharp_space_between_method_declaration_parameter_list_parentheses = false
csharp_space_between_parentheses = false
csharp_space_between_square_brackets = false

# Wrapping preferences
csharp_preserve_single_line_blocks = true
csharp_preserve_single_line_statements = true

# Naming Symbols

# constant_fields - Define constant fields
dotnet_naming_symbols.constant_fields.applicable_kinds                            = field
dotnet_naming_symbols.constant_fields.required_modifiers                          = const
# non_private_readonly_fields - Define public, internal and protected readonly fields
dotnet_naming_symbols.non_private_readonly_fields.applicable_accessibilities      = public, internal, protected
dotnet_naming_symbols.non_private_readonly_fields.applicable_kinds                = field
dotnet_naming_symbols.non_private_readonly_fields.required_modifiers              = readonly
# static_readonly_fields - Define static and readonly fields
dotnet_naming_symbols.static_readonly_fields.applicable_kinds                     = field
dotnet_naming_symbols.static_readonly_fields.required_modifiers                   = static, readonly
# private_readonly_fields - Define private readonly fields
dotnet_naming_symbols.private_readonly_fields.applicable_accessibilities          = private
dotnet_naming_symbols.private_readonly_fields.applicable_kinds                    = field
dotnet_naming_symbols.private_readonly_fields.required_modifiers                  = readonly
# public_internal_fields - Define public and internal fields
dotnet_naming_symbols.public_internal_protected_fields.applicable_accessibilities = public, internal, protected
dotnet_naming_symbols.public_internal_protected_fields.applicable_kinds           = field
# private_protected_fields - Define private and protected fields
dotnet_naming_symbols.private_protected_fields.applicable_accessibilities         = private, protected
dotnet_naming_symbols.private_protected_fields.applicable_kinds                   = field
# public_symbols - Define any public symbol
dotnet_naming_symbols.public_symbols.applicable_accessibilities                   = public, internal, protected, protected_internal
dotnet_naming_symbols.public_symbols.applicable_kinds                             = method, property, event, delegate
# parameters - Defines any parameter
dotnet_naming_symbols.parameters.applicable_kinds                                 = parameter
# non_interface_types - Defines class, struct, enum and delegate types
dotnet_naming_symbols.non_interface_types.applicable_kinds                        = class, struct, enum, delegate
# interface_types - Defines interfaces
dotnet_naming_symbols.interface_types.applicable_kinds                            = interface

# Naming Styles

# camel_case - Define the camelCase style
dotnet_naming_style.camel_case.capitalization                                     = camel_case
# pascal_case - Define the Pascal_case style
dotnet_naming_style.pascal_case.capitalization                                    = pascal_case
# first_upper - The first character must start with an upper-case character
dotnet_naming_style.first_upper.capitalization                                    = first_word_upper
# prefix_interface_interface_with_i - Interfaces must be PascalCase and the first character of an interface must be an &#39;I&#39;
dotnet_naming_style.prefix_interface_interface_with_i.capitalization              = pascal_case
dotnet_naming_style.prefix_interface_interface_with_i.required_prefix             = I

# Naming Rules

# Async
dotnet_naming_rule.async_methods_end_in_async.severity                            = silent
dotnet_naming_rule.async_methods_end_in_async.symbols                             = any_async_methods
dotnet_naming_rule.async_methods_end_in_async.style                               = end_in_async

dotnet_naming_symbols.any_async_methods.applicable_kinds                          = method
dotnet_naming_symbols.any_async_methods.applicable_accessibilities                = *
dotnet_naming_symbols.any_async_methods.required_modifiers                        = async

dotnet_naming_style.end_in_async.required_suffix                                  = Async
dotnet_naming_style.end_in_async.capitalization                                   = pascal_case

# Constant fields must be PascalCase
dotnet_naming_rule.constant_fields_must_be_pascal_case.severity                   = silent
dotnet_naming_rule.constant_fields_must_be_pascal_case.symbols                    = constant_fields
dotnet_naming_rule.constant_fields_must_be_pascal_case.style                      = pascal_case
# Public, internal and protected readonly fields must be PascalCase
dotnet_naming_rule.non_private_readonly_fields_must_be_pascal_case.severity       = silent
dotnet_naming_rule.non_private_readonly_fields_must_be_pascal_case.symbols        = non_private_readonly_fields
dotnet_naming_rule.non_private_readonly_fields_must_be_pascal_case.style          = pascal_case
# Static readonly fields must be PascalCase
dotnet_naming_rule.static_readonly_fields_must_be_pascal_case.severity            = silent
dotnet_naming_rule.static_readonly_fields_must_be_pascal_case.symbols             = static_readonly_fields
dotnet_naming_rule.static_readonly_fields_must_be_pascal_case.style               = pascal_case
# Private readonly fields must be camelCase
dotnet_naming_rule.private_readonly_fields_must_be_camel_case.severity            = silent
dotnet_naming_rule.private_readonly_fields_must_be_camel_case.symbols             = private_readonly_fields
dotnet_naming_rule.private_readonly_fields_must_be_camel_case.style               = camel_case
# Public and internal fields must be PascalCase
dotnet_naming_rule.public_internal_protected_fields_must_be_pascal_case.severity  = silent
dotnet_naming_rule.public_internal_protected_fields_must_be_pascal_case.symbols   = public_internal_protected_fields
dotnet_naming_rule.public_internal_protected_fields_must_be_pascal_case.style     = pascal_case
# Private and protected fields must be camelCase
dotnet_naming_rule.private_fields_must_be_camel_case.severity                     = silent
dotnet_naming_rule.private_fields_must_be_camel_case.symbols                      = private_protected_fields
dotnet_naming_rule.private_fields_must_be_camel_case.style                        = prefix_private_field_with_underscore
# Public members must be capitalized
dotnet_naming_rule.public_members_must_be_capitalized.severity                    = silent
dotnet_naming_rule.public_members_must_be_capitalized.symbols                     = public_symbols
dotnet_naming_rule.public_members_must_be_capitalized.style                       = first_upper
# Parameters must be camelCase
dotnet_naming_rule.parameters_must_be_camel_case.severity                         = silent
dotnet_naming_rule.parameters_must_be_camel_case.symbols                          = parameters
dotnet_naming_rule.parameters_must_be_camel_case.style                            = camel_case
# Class, struct, enum and delegates must be PascalCase
dotnet_naming_rule.non_interface_types_must_be_pascal_case.severity               = silent
dotnet_naming_rule.non_interface_types_must_be_pascal_case.symbols                = non_interface_types
dotnet_naming_rule.non_interface_types_must_be_pascal_case.style                  = pascal_case
# Interfaces must be PascalCase and start with an &#39;I&#39;
dotnet_naming_rule.interface_types_must_be_prefixed_with_i.severity               = silent
dotnet_naming_rule.interface_types_must_be_prefixed_with_i.symbols                = interface_types
dotnet_naming_rule.interface_types_must_be_prefixed_with_i.style                  = prefix_interface_interface_with_i
# prefix_private_field_with_underscore - Private fields must be prefixed with _
dotnet_naming_style.prefix_private_field_with_underscore.capitalization           = camel_case
dotnet_naming_style.prefix_private_field_with_underscore.required_prefix          = _

# .NET Code Analysis

dotnet_diagnostic.CA1001.severity = warning
dotnet_diagnostic.CA1009.severity = warning
dotnet_diagnostic.CA1016.severity = warning
dotnet_diagnostic.CA1033.severity = warning
dotnet_diagnostic.CA1049.severity = warning
dotnet_diagnostic.CA1060.severity = warning
dotnet_diagnostic.CA1061.severity = warning
dotnet_diagnostic.CA1063.severity = warning
dotnet_diagnostic.CA1065.severity = warning
dotnet_diagnostic.CA1301.severity = warning
dotnet_diagnostic.CA1400.severity = warning
dotnet_diagnostic.CA1401.severity = warning
dotnet_diagnostic.CA1403.severity = warning
dotnet_diagnostic.CA1404.severity = warning
dotnet_diagnostic.CA1405.severity = warning
dotnet_diagnostic.CA1410.severity = warning
dotnet_diagnostic.CA1415.severity = warning
dotnet_diagnostic.CA1821.severity = warning
dotnet_diagnostic.CA1900.severity = warning
dotnet_diagnostic.CA1901.severity = warning
dotnet_diagnostic.CA2002.severity = warning
dotnet_diagnostic.CA2100.severity = warning
dotnet_diagnostic.CA2101.severity = warning
dotnet_diagnostic.CA2108.severity = warning
dotnet_diagnostic.CA2111.severity = warning
dotnet_diagnostic.CA2112.severity = warning
dotnet_diagnostic.CA2114.severity = warning
dotnet_diagnostic.CA2116.severity = warning
dotnet_diagnostic.CA2117.severity = warning
dotnet_diagnostic.CA2122.severity = warning
dotnet_diagnostic.CA2123.severity = warning
dotnet_diagnostic.CA2124.severity = warning
dotnet_diagnostic.CA2126.severity = warning
dotnet_diagnostic.CA2131.severity = warning
dotnet_diagnostic.CA2132.severity = warning
dotnet_diagnostic.CA2133.severity = warning
dotnet_diagnostic.CA2134.severity = warning
dotnet_diagnostic.CA2137.severity = warning
dotnet_diagnostic.CA2138.severity = warning
dotnet_diagnostic.CA2140.severity = warning
dotnet_diagnostic.CA2141.severity = warning
dotnet_diagnostic.CA2146.severity = warning
dotnet_diagnostic.CA2147.severity = warning
dotnet_diagnostic.CA2149.severity = warning
dotnet_diagnostic.CA2200.severity = warning
dotnet_diagnostic.CA2202.severity = warning
dotnet_diagnostic.CA2207.severity = warning
dotnet_diagnostic.CA2212.severity = warning
dotnet_diagnostic.CA2213.severity = warning
dotnet_diagnostic.CA2214.severity = warning
dotnet_diagnostic.CA2216.severity = warning
dotnet_diagnostic.CA2220.severity = warning
dotnet_diagnostic.CA2229.severity = warning
dotnet_diagnostic.CA2231.severity = warning
dotnet_diagnostic.CA2232.severity = warning
dotnet_diagnostic.CA2235.severity = warning
dotnet_diagnostic.CA2236.severity = warning
dotnet_diagnostic.CA2237.severity = warning
dotnet_diagnostic.CA2238.severity = warning
dotnet_diagnostic.CA2240.severity = warning
dotnet_diagnostic.CA2241.severity = warning
dotnet_diagnostic.CA2242.severity = warning

# Require file header OR A source file contains a header that does not match the required text
dotnet_diagnostic.IDE0073.severity = error

# StyleCop Code Analysis

# Closing parenthesis should be spaced correctly: &quot;foo()!&quot;
dotnet_diagnostic.SA1009.severity = none

# Hide warnings when using the new() expression from C# 9.
dotnet_diagnostic.SA1000.severity = none

dotnet_diagnostic.SA1011.severity = none
dotnet_diagnostic.SA1101.severity = none

# Hide warnings when accessing properties without &quot;this&quot;.
dotnet_diagnostic.SA1101.severity = none
dotnet_diagnostic.SA1118.severity = none
dotnet_diagnostic.SA1200.severity = none
dotnet_diagnostic.SA1201.severity = none
dotnet_diagnostic.SA1202.severity = none
dotnet_diagnostic.SA1309.severity = none
dotnet_diagnostic.SA1310.severity = none

# Hide warnings for record parameters.
dotnet_diagnostic.SA1313.severity = none

# TypeParameterNamesMustBeginWithT: We do have a few templates that don&#39;t start with T. We need to double check that changing this is not a breaking change. If not, we can re-enable this.
dotnet_diagnostic.SA1314.severity = none

# UseTrailingCommasInMultiLineInitializers: This would also mean a lot of changes at the end of all multiline initializers. It&#39;s also debatable if we want this or not.
dotnet_diagnostic.SA1413.severity = none

dotnet_diagnostic.SA1600.severity = none
dotnet_diagnostic.SA1602.severity = none
dotnet_diagnostic.SA1611.severity = none

# DocumentationTextMustEndWithAPeriod: Let&#39;s enable this rule back when we shift to WinUI3 (v8.x). If we do it now, it would mean more than 400 file changes.
dotnet_diagnostic.SA1629.severity = none

dotnet_diagnostic.SA1633.severity = none
dotnet_diagnostic.SA1634.severity = none
dotnet_diagnostic.SA1652.severity = none

Setting up Git Pre-Commit Hooks

For this Pre-Commit Hook to work, we are going to be using dotnet format. This Powershell command applies style preferences from your .editorconfig file. We want to go into our .git\hooks folder and copy and paste pre-commit.sample . We want to rename that copied file to be pre-commit.

Inside the new pre-commit file, open it up using notepad or vim and add this to the file:

#!/bin/sh

dotnet format ./PreCommitHookFormatExample.sln --verify-no-changes

Watch Magic Happen

Inside of Powershell or Terminal, go to your project location and execute git add . and git commit -m "<Insert Message>" . If you get a series of messages like this, the git hook is working correctly:

With this git hook in place, everything will be checked against the .editorconfig file. Anything that is not following standards will notify me and I can make those edits before it lands inside of GitHub. The likelihood of broken linting builds is dramatically reduced.

If you have any questions, comments, or suggestions, please feel free to drop a response to this article.

Until then, I’ll see you next time.

Documentation

Microsoft’s dotnet format documentation

Microsoft’s editorconfig Documentation