This is likely to be a rather tedious undertaking, since all of the parameter lists in theme_data.dart are supposed to be in the same order (for our own sanity). If you're going to categorize the theme data properties, it would be helpful to highlight the ones whose lifetime is limited per flutter.dev/go/material-theme-system-updates and the upcoming move to Material 3.

That said, if you'd really like to improve the readability of this file, go for it.

I'm torn between my laziness and love for neatness. I think I'll do just categorization and forgo alphabetization

@HansMuller I went ahead and did the whole thing. Don't ever make me do that again (kidding)

@rami-a Can you provide color (ha) into which color properties–if any–will be repurposed for material 3? #89852

Also, I'll add tests for debugFillProperties

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@guidezpl, sorry I didn't catch this sooner. I thought you were just updating the parameters to the default constructor. I was also working in this area with #91774 which will now likely conflict with anything you do in the rest of the file. We should coordinate so we don't step on each others changes.

As for which colors will be repurposed for M3, none of the top level color parameters in the ThemeData will be needed, as they are mostly just for backwards compatibility at this point. M3 will be using the colors from the colorScheme exclusively.

Np, please merge your change first, it'll easier for me to merge it into mine afterwards.

That was my understanding as well, sounds good.

Np, please merge your change first, it'll easier for me to merge it into mine afterwards.

Will do. Unfortunately there was a revert on master that is causing a merge issue for my PR. Once I get that sorted out I will land it this morning.

I noticed that platform defines defaults for typography and materialTapTargetSize but wasn't documented. I added missing explanations

@HansMuller I'm running into a failed test for the backwards compatibility for deprecated buttons' highlight color. e.g. In theme_defaults_test.dart, a RaisedButton is expected to have a highlight color of 0x29000000, but I'm getting 0x66bcbcbc. This is noted in the comments as "// Was Color(0x66bcbcbc)". Can you help me understand this change in default?

The line you're referring to was added about 3 years ago (https://github.com/flutter/flutter/pull/22013/files#diff-7ba6209c92d2c9f5eaedb3ae9336f9c7049aedff35e18c697150a64317fd79e7R31) and I don't think I can offer an explanation for that. I assume that something is slightly out of order WRT the ThemeData initializations, but couldn't tell you more without really digging in.

Thanks, fixed that. Good to review

Wow, thanks @guidezpl! For us that reads ThemeData a lot this is really useful and nice! 💙