add comment to explain scroll to bottom

[srikarparsi]

Details

Add comment to explain that the chat is supposed to scroll to the bottom once new messages is clicked and not to the last unread message. Most methods around it also have comments explaining the method so would be similar

Fixed Issues

$ N/A (Should I create an issue for just adding a comment?)
PROPOSAL: GH_LINK_ISSUE(COMMENT)

Tests

• Verify that no errors appear in the JS console

Offline tests

QA Steps

• Verify that no errors appear in the JS console

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • iOS / native
  • Android / native
  • iOS / Safari
  • Android / Chrome
  • MacOS / Chrome
  • MacOS / Desktop
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I followed proper code patterns (see Reviewing the code)
  • I verified that any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text shown in the product was added in all src/languages/* files
  • I verified any copy / text that was added to the app is correct English and approved by marketing by adding the Waiting for Copy label for a copy review on the original GH to get the correct copy.
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.js or at the top of the file that uses the constant) are defined as such
• I verified that if a function's arguments changed that all usages have also been updated correctly
• If a new component is created I verified that:
  • A similar component doesn't exist in the codebase
  • All props are defined accurately and each prop has a /** comment above it */
  • The file is named correctly
  • The component has a clear name that is non-ambiguous and the purpose of the component can be inferred from the name alone
  • The only data being stored in the state is data necessary for rendering and nothing else
  • For Class Components, any internal methods passed to components event handlers are bound to this properly so there are no scoping issues (i.e. for onClick={this.submit} the method this.submit should be bound to this in the constructor)
  • Any internal methods bound to this are necessary to be bound (i.e. avoid this.submit = this.submit.bind(this); if this.submit is never passed to a component event handler like onClick)
  • All JSX used for rendering exists in the render method
  • The component has the minimum amount of code necessary for its purpose, and it is broken down into smaller components in order to separate concerns and functions
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(themeColors.componentBG)
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If a new page is added, I verified it's using the ScrollView component to make it scrollable when more elements are added to the page.
• I have checked off every checkbox in the PR author checklist, including those that don't apply to this PR.

Screenshots/Videos

Web

N/A

Mobile Web - Chrome

N/A

Mobile Web - Safari

N/A

Desktop

N/A

iOS

N/A

Android

N/A

[melvin-bot]

@MariaHCD Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[MariaHCD]

Just to clarify, are we planning to alter this behavior in the future?

[marcaaron]

I don't really think this change is needed. It won't really prevent anyone from changing anything if they are determined to do so.

[marcaaron]

Also we should not say where a function will be used in a comment. It could be used in multiple places and you can search to see where it is actually used.

[srikarparsi]

Yeah that makes sense - I just added a use case since I saw it done in the comment below it but yeah new use cases could be made for that method. I think that it just adds another layer that someone would have to make to change this behavior and would be more easily caught since it's a comment which is clearer than a method name. I also don't think the change has any drawbacks but if you don't think it's necessary at all, I can close out this PR.

[srikarparsi]

And I'm not sure @MariaHCD, I was talking to Marc about this last week and understood that we're trying to implement bidirectional scrolling which would help in situations like this but I'm not sure if we have plans to change the functionality of when someone clicks "New Messages"

[marcaaron]

Personally, I think we should close this. We have no way of knowing whether this comment will help avoid any future or past situation. The content can also be extracted by looking at the method name and then looking at where it's used.

[srikarparsi]

Yeah you're right, that makes sense so I'll close out this PR 👍🏾