Implement SA1138: Indent elements correctly

[sharwell]

Category: Readability
Title: Indent elements correctly
Description: A line of code is not indented the correct amount, according to the currently applied style settings for the project.

This rule is intended to be a general rule which will eventually enforce indentation according to policies defined in stylecop.json. This rule works alongside SA1137 (#2023) to increase the overall consistency of indentation in the project. The initial implementation will consist of the following specific behaviors to match settings exposed in Visual Studio:

1. CSharpFormattingOptions.IndentBlock (override with indentBlock option in stylecop.json)
2. CSharpFormattingOptions.IndentSwitchSection (override with indentSwitchSection in stylecop.json)
3. CSharpFormattingOptions.IndentSwitchCaseSection (override with indentSwitchCaseSection in stylecop.json)
4. CSharpFormattingOptions.LabelPositioning (override with labelPositioning in stylecop.json)

[nbarbettini]

I'm not completely clear on the relationship between this and #2023. Is this more specific than SA1137, or less?

[sharwell]

@nbarbettini Theoretically this rule could become more specific than SA1137 in the future, but we're a long way from that. Right now the two rules only partially overlap. For example, SA1137 ensures that when wrapping a method invocation so each argument is on its own line, those arguments are indented the same amount. The rule proposed here does not examine arguments at all. The goal is to progressively build up a flexible solution for indentation as a series of smaller steps.

Right now I'm only planning to include two rules:

1. SA1137: This checks relative indentation of elements within a single group in isolation. It probably won't need the ability to configure it, and I don't expect users to find it problematic.
2. The rule proposed here: For supported elements, this checks the absolute indentation of the elements. It will require a fairly large number of options to support various indentation requirements of projects.

[nbarbettini]

Makes perfect sense now. 👍 on this.

[Noryoko]

👍 From me. I'm particularly interested in items 2 and 3.

[vweijsters]

👍

[sharwell]

Well, we can't use or reference the predefined formatting options from the analyzer, since they are defined in the workspaces assembly that isn't available during analysis (only during code fixes). So the behavior of null for each of these properties is to simply ignore the indentation of that item relative to its parent.

[abhiyadav1323]

Is there any progress on this?

[zmarty]

We need this too :)

[samuel-knutson]

Any update? Very much looking forward to this rule. Right now, StyleCop doesn't complain about code like this:

  public class DateTimeProvider : IDateTimeProvider
    {
          public DateTime Now()
                {
            return DateTime.Now;
            }
                    }

Thanks for all your work on this project BTW!