Better best effort type alias preservation

[Wesley Wigham (weswigham)]

In this PR, we record all[1] aliases we create for a type, rather than just the one we encounter on the adjacent declaration the first time we create a type, and then use that recorded list of aliases to improve declaration emit/printback in a more deterministic way.

Fixes #40092 and probably a lot of other stuff. I've labeled this as a potentially Breaking Change as the use of more aliases could affect people's declaration emit of inferred types - for example, the lib PropertyKey type is often used in place of string | number | symbol (since it's a global type alias).

[1]some aliases we could make, but likely just increase complexity, are intentionally omitted - this way we don't do things like printback NonNullable<NonNullable<T>> as a preferred "alias" of T.

[Wesley Wigham (weswigham)]

TypeScript Bot (@typescript-bot) perf test this (this almost certainly has a cost)
TypeScript Bot (@typescript-bot) user test this
TypeScript Bot (@typescript-bot) run dt

TypeScript Bot (@typescript-bot) pack this

[TypeScript Bot (typescript-bot)]

Heya Wesley Wigham (@weswigham), I've started to run the tarball bundle task on this PR at 7d9bb77. You can monitor the build here.

[TypeScript Bot (typescript-bot)]

Heya Wesley Wigham (@weswigham), I've started to run the perf test suite on this PR at 7d9bb77. You can monitor the build here.

Update: The results are in!

[TypeScript Bot (typescript-bot)]

Heya Wesley Wigham (@weswigham), I've started to run the parallelized community code test suite on this PR at 7d9bb77. You can monitor the build here.

[TypeScript Bot (typescript-bot)]

Heya Wesley Wigham (@weswigham), I've started to run the parallelized Definitely Typed test suite on this PR at 7d9bb77. You can monitor the build here.

[TypeScript Bot (typescript-bot)]

The user suite test run you requested has finished and failed. I've opened a PR with the baseline diff from master.

[TypeScript Bot (typescript-bot)]

Wesley Wigham (@weswigham)
The results of the perf run you requested are in!

Here they are:

Comparison Report - master..40232

Metric	master	40232	Delta	Best	Worst
Angular - node (v10.16.3, x64)
Memory used	344,453k (± 0.02%)	345,850k (± 0.01%)	+1,397k (+ 0.41%)	345,753k	345,996k
Parse Time	2.02s (± 0.58%)	2.00s (± 0.50%)	-0.02s (- 0.94%)	1.98s	2.03s
Bind Time	0.83s (± 1.89%)	0.82s (± 0.54%)	-0.00s (- 0.48%)	0.81s	0.83s
Check Time	4.80s (± 0.62%)	4.79s (± 0.40%)	-0.01s (- 0.19%)	4.75s	4.83s
Emit Time	5.18s (± 0.68%)	5.19s (± 0.56%)	+0.01s (+ 0.14%)	5.11s	5.24s
Total Time	12.82s (± 0.54%)	12.79s (± 0.31%)	-0.03s (- 0.21%)	12.71s	12.89s
Monaco - node (v10.16.3, x64)
Memory used	339,280k (± 0.04%)	339,566k (± 0.03%)	+286k (+ 0.08%)	339,363k	339,795k
Parse Time	1.56s (± 0.89%)	1.55s (± 0.66%)	-0.01s (- 0.45%)	1.53s	1.58s
Bind Time	0.71s (± 0.31%)	0.71s (± 0.63%)	-0.00s (- 0.42%)	0.70s	0.72s
Check Time	4.95s (± 0.71%)	4.96s (± 0.43%)	+0.01s (+ 0.24%)	4.92s	5.02s
Emit Time	2.74s (± 1.08%)	2.74s (± 0.52%)	-0.01s (- 0.22%)	2.70s	2.76s
Total Time	9.96s (± 0.67%)	9.96s (± 0.36%)	-0.00s (- 0.03%)	9.90s	10.07s
TFS - node (v10.16.3, x64)
Memory used	302,273k (± 0.03%)	302,596k (± 0.04%)	+323k (+ 0.11%)	302,317k	302,782k
Parse Time	1.21s (± 0.56%)	1.21s (± 0.66%)	+0.00s (+ 0.17%)	1.19s	1.23s
Bind Time	0.67s (± 1.04%)	0.67s (± 0.87%)	-0.00s (- 0.60%)	0.65s	0.68s
Check Time	4.44s (± 0.83%)	4.46s (± 0.62%)	+0.02s (+ 0.38%)	4.39s	4.54s
Emit Time	2.92s (± 0.72%)	2.89s (± 0.88%)	-0.03s (- 1.03%)	2.84s	2.93s
Total Time	9.23s (± 0.65%)	9.22s (± 0.48%)	-0.01s (- 0.14%)	9.12s	9.33s
material-ui - node (v10.16.3, x64)
Memory used	460,841k (± 0.01%)	475,192k (± 0.02%)	+14,352k (+ 3.11%)	475,050k	475,388k
Parse Time	1.95s (± 0.30%)	1.95s (± 0.38%)	+0.00s (+ 0.00%)	1.94s	1.97s
Bind Time	0.66s (± 1.10%)	0.66s (± 1.04%)	-0.01s (- 0.91%)	0.64s	0.67s
Check Time	13.51s (± 0.84%)	15.67s (± 0.65%)	+2.16s (+15.99%)	15.51s	15.95s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	16.13s (± 0.72%)	18.28s (± 0.58%)	+2.16s (+13.36%)	18.12s	18.58s
Angular - node (v12.1.0, x64)
Memory used	321,740k (± 0.03%)	323,094k (± 0.03%)	+1,353k (+ 0.42%)	322,936k	323,362k
Parse Time	1.99s (± 0.56%)	1.96s (± 0.54%)	-0.03s (- 1.55%)	1.95s	2.00s
Bind Time	0.81s (± 0.61%)	0.80s (± 0.72%)	-0.00s (- 0.37%)	0.79s	0.82s
Check Time	4.68s (± 0.56%)	4.67s (± 0.32%)	-0.00s (- 0.09%)	4.65s	4.71s
Emit Time	5.36s (± 0.61%)	5.37s (± 0.58%)	+0.01s (+ 0.22%)	5.33s	5.47s
Total Time	12.83s (± 0.45%)	12.81s (± 0.30%)	-0.03s (- 0.21%)	12.74s	12.94s
Monaco - node (v12.1.0, x64)
Memory used	321,551k (± 0.01%)	322,056k (± 0.02%)	+505k (+ 0.16%)	321,900k	322,223k
Parse Time	1.53s (± 0.74%)	1.52s (± 1.02%)	-0.01s (- 0.39%)	1.50s	1.58s
Bind Time	0.69s (± 0.81%)	0.69s (± 0.98%)	+0.01s (+ 0.87%)	0.69s	0.72s
Check Time	4.74s (± 0.30%)	4.74s (± 0.49%)	-0.00s (- 0.04%)	4.68s	4.79s
Emit Time	2.79s (± 0.66%)	2.79s (± 0.47%)	+0.00s (+ 0.14%)	2.77s	2.82s
Total Time	9.75s (± 0.42%)	9.75s (± 0.30%)	+0.00s (+ 0.01%)	9.69s	9.83s
TFS - node (v12.1.0, x64)
Memory used	286,603k (± 0.03%)	286,952k (± 0.02%)	+349k (+ 0.12%)	286,842k	287,165k
Parse Time	1.23s (± 1.05%)	1.23s (± 0.48%)	-0.00s (- 0.08%)	1.22s	1.24s
Bind Time	0.64s (± 0.87%)	0.64s (± 0.73%)	+0.00s (+ 0.31%)	0.63s	0.65s
Check Time	4.36s (± 0.48%)	4.35s (± 0.30%)	-0.00s (- 0.05%)	4.32s	4.37s
Emit Time	2.93s (± 0.62%)	2.91s (± 0.75%)	-0.02s (- 0.58%)	2.87s	2.97s
Total Time	9.15s (± 0.36%)	9.13s (± 0.33%)	-0.02s (- 0.21%)	9.05s	9.20s
material-ui - node (v12.1.0, x64)
Memory used	439,051k (± 0.07%)	453,066k (± 0.07%)	+14,014k (+ 3.19%)	452,273k	453,736k
Parse Time	1.99s (± 0.48%)	1.96s (± 0.38%)	-0.03s (- 1.31%)	1.94s	1.97s
Bind Time	0.64s (± 0.70%)	0.62s (± 0.93%)	-0.02s (- 2.82%)	0.61s	0.63s
Check Time	12.02s (± 0.80%)	14.24s (± 1.07%)	+2.22s (+18.47%)	13.99s	14.56s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	14.64s (± 0.69%)	16.82s (± 0.90%)	+2.18s (+14.88%)	16.59s	17.14s
Angular - node (v8.9.0, x64)
Memory used	341,072k (± 0.01%)	342,389k (± 0.01%)	+1,317k (+ 0.39%)	342,280k	342,488k
Parse Time	2.55s (± 0.51%)	2.54s (± 0.42%)	-0.01s (- 0.39%)	2.52s	2.56s
Bind Time	0.86s (± 1.34%)	0.85s (± 0.76%)	-0.01s (- 1.40%)	0.83s	0.86s
Check Time	5.40s (± 0.89%)	5.46s (± 0.48%)	+0.06s (+ 1.07%)	5.40s	5.51s
Emit Time	6.06s (± 1.48%)	5.93s (± 2.13%)	-0.13s (- 2.23%)	5.68s	6.22s
Total Time	14.86s (± 0.72%)	14.77s (± 0.86%)	-0.09s (- 0.63%)	14.48s	15.09s
Monaco - node (v8.9.0, x64)
Memory used	340,580k (± 0.01%)	341,083k (± 0.01%)	+502k (+ 0.15%)	340,984k	341,169k
Parse Time	1.87s (± 0.56%)	1.88s (± 0.27%)	+0.00s (+ 0.11%)	1.87s	1.89s
Bind Time	0.88s (± 0.53%)	0.88s (± 0.59%)	+0.00s (+ 0.11%)	0.87s	0.89s
Check Time	5.48s (± 0.60%)	5.49s (± 0.50%)	+0.01s (+ 0.20%)	5.44s	5.54s
Emit Time	3.19s (± 0.50%)	3.23s (± 0.39%)	+0.04s (+ 1.13%)	3.20s	3.25s
Total Time	11.42s (± 0.32%)	11.47s (± 0.34%)	+0.05s (+ 0.44%)	11.40s	11.55s
TFS - node (v8.9.0, x64)
Memory used	303,884k (± 0.02%)	304,227k (± 0.02%)	+343k (+ 0.11%)	304,066k	304,317k
Parse Time	1.54s (± 0.45%)	1.55s (± 0.68%)	+0.01s (+ 0.39%)	1.53s	1.57s
Bind Time	0.67s (± 0.86%)	0.67s (± 0.86%)	-0.00s (- 0.00%)	0.66s	0.68s
Check Time	5.20s (± 0.56%)	5.22s (± 0.54%)	+0.03s (+ 0.48%)	5.16s	5.30s
Emit Time	2.93s (± 0.63%)	2.93s (± 0.63%)	+0.00s (+ 0.10%)	2.89s	2.96s
Total Time	10.33s (± 0.37%)	10.37s (± 0.37%)	+0.03s (+ 0.31%)	10.28s	10.47s
material-ui - node (v8.9.0, x64)
Memory used	465,199k (± 0.01%)	479,916k (± 0.01%)	+14,717k (+ 3.16%)	479,768k	480,127k
Parse Time	2.40s (± 0.46%)	2.38s (± 0.60%)	-0.02s (- 0.67%)	2.36s	2.42s
Bind Time	0.77s (± 1.07%)	0.78s (± 1.35%)	+0.01s (+ 0.78%)	0.76s	0.81s
Check Time	18.05s (± 0.77%)	22.71s (± 1.50%)	+4.66s (+25.82%)	22.14s	23.49s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	21.22s (± 0.68%)	25.87s (± 1.36%)	+4.65s (+21.91%)	25.27s	26.69s
Angular - node (v8.9.0, x86)
Memory used	195,727k (± 0.01%)	196,338k (± 0.02%)	+612k (+ 0.31%)	196,267k	196,411k
Parse Time	2.46s (± 0.56%)	2.46s (± 0.59%)	-0.00s (- 0.12%)	2.42s	2.49s
Bind Time	1.00s (± 0.80%)	0.99s (± 0.74%)	-0.01s (- 1.40%)	0.98s	1.01s
Check Time	4.89s (± 0.52%)	4.89s (± 0.63%)	-0.00s (- 0.04%)	4.83s	4.98s
Emit Time	5.95s (± 0.90%)	5.98s (± 1.18%)	+0.03s (+ 0.54%)	5.90s	6.20s
Total Time	14.30s (± 0.47%)	14.31s (± 0.76%)	+0.01s (+ 0.07%)	14.19s	14.69s
Monaco - node (v8.9.0, x86)
Memory used	193,625k (± 0.02%)	193,885k (± 0.02%)	+261k (+ 0.13%)	193,805k	194,009k
Parse Time	1.92s (± 0.78%)	1.90s (± 0.58%)	-0.01s (- 0.68%)	1.89s	1.93s
Bind Time	0.70s (± 0.95%)	0.70s (± 0.71%)	-0.00s (- 0.57%)	0.69s	0.71s
Check Time	5.57s (± 0.59%)	5.61s (± 0.62%)	+0.04s (+ 0.63%)	5.54s	5.70s
Emit Time	2.67s (± 0.92%)	2.67s (± 1.29%)	-0.01s (- 0.26%)	2.63s	2.79s
Total Time	10.86s (± 0.51%)	10.88s (± 0.48%)	+0.01s (+ 0.11%)	10.76s	11.00s
TFS - node (v8.9.0, x86)
Memory used	173,848k (± 0.03%)	174,057k (± 0.03%)	+209k (+ 0.12%)	173,951k	174,250k
Parse Time	1.59s (± 0.84%)	1.59s (± 0.96%)	0.00s ( 0.00%)	1.56s	1.64s
Bind Time	0.64s (± 0.62%)	0.64s (± 0.35%)	0.00s ( 0.00%)	0.64s	0.65s
Check Time	4.72s (± 0.60%)	4.74s (± 0.65%)	+0.02s (+ 0.34%)	4.65s	4.78s
Emit Time	2.80s (± 1.20%)	2.79s (± 0.68%)	-0.01s (- 0.39%)	2.75s	2.83s
Total Time	9.75s (± 0.48%)	9.75s (± 0.53%)	+0.01s (+ 0.05%)	9.63s	9.89s
material-ui - node (v8.9.0, x86)
Memory used	263,437k (± 0.01%)	270,938k (± 0.02%)	+7,501k (+ 2.85%)	270,827k	271,045k
Parse Time	2.45s (± 0.68%)	2.45s (± 1.02%)	-0.00s (- 0.08%)	2.40s	2.53s
Bind Time	0.67s (± 0.92%)	0.67s (± 1.52%)	+0.00s (+ 0.30%)	0.66s	0.70s
Check Time	16.47s (± 0.76%)	21.10s (± 1.43%)	+4.63s (+28.11%)	20.66s	21.86s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	19.59s (± 0.68%)	24.22s (± 1.22%)	+4.63s (+23.63%)	23.73s	24.94s

System

Machine Name	ts-ci-ubuntu
Platform	linux 4.4.0-166-generic
Architecture	x64
Available Memory	16 GB
Available Memory	1 GB
CPUs	4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz

Hosts

• node (v10.16.3, x64)
• node (v12.1.0, x64)
• node (v8.9.0, x64)
• node (v8.9.0, x86)

Scenarios

• Angular - node (v10.16.3, x64)
• Angular - node (v12.1.0, x64)
• Angular - node (v8.9.0, x64)
• Angular - node (v8.9.0, x86)
• Monaco - node (v10.16.3, x64)
• Monaco - node (v12.1.0, x64)
• Monaco - node (v8.9.0, x64)
• Monaco - node (v8.9.0, x86)
• TFS - node (v10.16.3, x64)
• TFS - node (v12.1.0, x64)
• TFS - node (v8.9.0, x64)
• TFS - node (v8.9.0, x86)
• material-ui - node (v10.16.3, x64)
• material-ui - node (v12.1.0, x64)
• material-ui - node (v8.9.0, x64)
• material-ui - node (v8.9.0, x86)

Benchmark	Name	Iterations
Current	40232	10
Baseline	master	10

[Sebastian Nemeth (martaver)]

Does this PR address the non-propogation of type aliases described in point one in #45954, which makes proposals to Improve type readability?

[Nathan Shively-Sanders (sandersn)]

Unfortunately, we never finished reviewing this PR. It is pretty old now, so I'm going to close it to reduce the number of open PRs.