fix: Visualization settings were lost when editing a datasource from Explore

[willbarrett]

SUMMARY

When working on a visualization in Explore, if there were changes to the visualization that had not been "run" via the "Run Query" button, they would be lost when editing the related datasource via the modal on the page.

Why? The reducer that updated the form_data when a form component changed was broken in such a way that it would update the control settings to make the change visible, but not the form_data settings to make the change durable.

This PR retains the behavior of not updating the encoded data in the URL until the "Run Query" button is pressed.

Question for the community: are there any tests for any of the reducers in Superset? Can someone point me to an example? I'd love to write some tests for this change to avoid a regression.

Also, big props to @nytai for walking me through the Explore front-end code and helping me track this one down.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TEST PLAN

• Open the Explore view by creating an arbitrary query in SQL Lab and clicking Explore
• Enter some chart options
• Edit the dataset by using the dropdown
• Click Save in the modal
• Click Confirm
• The chart options you had selected before editing the dataset should still be present.

ADDITIONAL INFORMATION

• Has associated issue:
• Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

[nytai]

@willbarrett there are a few tests for the exploreReducer here

[willbarrett]

Thanks @nytai - I'll add a few more.

[ktmud]

I also noticed this yesterday and was surprised. Thanks for the fix!

[willbarrett]

@nytai @ktmud @etr2460 I believe this is ready for review, when you have a moment.

[codecov-commenter]

Codecov Report

Merging #10092 into master will decrease coverage by 4.83%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master   #10092      +/-   ##
==========================================
- Coverage   70.63%   65.80%   -4.84%     
==========================================
  Files         592      590       -2     
  Lines       31191    31139      -52     
  Branches     3191     3163      -28     
==========================================
- Hits        22032    20490    -1542     
- Misses       9050    10471    +1421     
- Partials      109      178      +69     

Flag	Coverage Δ
#cypress	?
#javascript	59.55% <100.00%> (-0.19%)	⬇️
#python	70.21% <ø> (+0.02%)	⬆️

Impacted Files	Coverage Δ
...et-frontend/src/explore/reducers/exploreReducer.js	26.41% <100.00%> (-4.50%)	⬇️
superset-frontend/src/SqlLab/App.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/explore/App.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/SqlLab/index.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/dashboard/App.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/explore/index.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/dashboard/index.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/setup/setupColors.js	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/chart/ChartContainer.jsx	0.00% <0.00%> (-100.00%)	⬇️
superset-frontend/src/setup/setupFormatters.js	0.00% <0.00%> (-100.00%)	⬇️
... and 147 more

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[ktmud]

Code LGTM.

Just a note that this will also keep the settings when changing to a different datasource, which leaves invalid selected columns sometimes (probably doesn't matter though).

[etr2460]

lgtm, assuming the tests failed before making this change. and thanks so much for tracking this bug down!

also, could you add a test plan to the summary prior to merging? Thanks!