fix(types): correct types when middleware return Promise<void>

[yusukebe]

Fixes #4517

The author should do the following, if applicable

• [ ] Add tests
• [ ] Run tests
• [ ] bun run format:fix && bun run lint:fix to format the code
• [ ] Add TSDoc/JSDoc to document the code

[github-actions[bot]]

Bundle size check

	main (8fe7fee)	#4529 (98b6287)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (8fe7fee)	#4529 (98b6287)	+/-
Files	303	303	0
Lines	140,900	140,916	16
Identifiers	128,526	128,544	18
Symbols	269,140	269,183	43
Types	198,856	201,545	2,689
Instantiations	639,355	657,625	18,270
Memory used	350,260K	358,685K	8,425K
I/O read	0.02s	0.02s	0s
I/O write	0s	0s	0s
Parse time	0.84s	0.72s	-0.12s
Bind time	0.37s	0.31s	-0.06s
Check time	3.34s	2.98s	-0.36s
Emit time	0s	0s	0s
Total time	4.55s	4.02s	-0.53s

Compiler Diagnostics (typescript-go)

	main (8fe7fee)	#4529 (98b6287)	+/-
Files	272	272	0
Lines	118,789	118,805	16
Identifiers	117,959	117,977	18
Symbols	378,470	378,586	116
Types	360,479	364,398	3,919
Instantiations	3,764,726	3,797,300	32,574
Memory used	250,891K	252,148K	1,257K
Memory allocs	10,583,219	10,627,439	44,220
Parse time	0.089s	0.094s	0.005s
Bind time	0.048s	0.04s	-0.008s
Check time	1.476s	1.688s	0.212s
Emit time	0s	0s	0s
Total time	1.617s	1.826s	0.209s

---

Reported by octocov

[github-actions[bot]]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	37,957.57	51,751.26	33,697.84	28,423.60
hono (current)	bun	37,891.61	50,851.11	33,972.34	28,851.39
Change		-0.17%	-1.74%	+0.81%	+1.51%

[github-actions[bot]]

Bundle size check

	main (342ff3b)	#4529 (fbf6b04)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (342ff3b)	#4529 (fbf6b04)	+/-
Files	303	303	0
Lines	140,900	140,916	16
Identifiers	128,526	128,544	18
Symbols	269,140	269,183	43
Types	198,856	201,545	2,689
Instantiations	639,355	657,625	18,270
Memory used	371,793K	358,518K	-13,275K
I/O read	0.04s	0.02s	-0.02s
I/O write	0s	0s	0s
Parse time	0.74s	0.71s	-0.03s
Bind time	0.3s	0.29s	-0.01s
Check time	2.83s	3.15s	0.32s
Emit time	0s	0s	0s
Total time	3.87s	4.15s	0.28s

Compiler Diagnostics (typescript-go)

	main (342ff3b)	#4529 (fbf6b04)	+/-
Files	272	272	0
Lines	118,789	118,805	16
Identifiers	117,959	117,977	18
Symbols	378,470	378,586	116
Types	360,479	364,398	3,919
Instantiations	3,764,726	3,797,300	32,574
Memory used	250,948K	252,224K	1,276K
Memory allocs	10,583,093	10,627,567	44,474
Parse time	0.071s	0.094s	0.023s
Bind time	0.027s	0.027s	0s
Check time	1.542s	1.563s	0.021s
Emit time	0s	0s	0s
Total time	1.65s	1.698s	0.048s

---

Reported by octocov

[github-actions[bot]]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	37,898.49	51,988.80	34,006.93	27,699.74
hono (current)	bun	37,684.05	52,296.17	33,407.78	27,348.19
Change		-0.57%	+0.59%	-1.76%	-1.27%

[github-actions[bot]]

Bundle size check

	main (342ff3b)	#4529 (e338371)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (342ff3b)	#4529 (e338371)	+/-
Files	303	303	0
Lines	140,900	140,934	34
Identifiers	128,526	128,572	46
Symbols	269,140	289,648	20,508
Types	198,856	205,193	6,337
Instantiations	639,355	1,041,936	402,581
Memory used	371,793K	400,546K	28,753K
I/O read	0.04s	0.03s	-0.01s
I/O write	0s	0s	0s
Parse time	0.74s	0.73s	-0.01s
Bind time	0.3s	0.3s	0s
Check time	2.83s	3.6s	0.77s
Emit time	0s	0s	0s
Total time	3.87s	4.64s	0.77s

Compiler Diagnostics (typescript-go)

	main (342ff3b)	#4529 (e338371)	+/-
Files	272	272	0
Lines	118,789	118,823	34
Identifiers	117,959	118,005	46
Symbols	378,470	419,425	40,955
Types	360,479	372,078	11,599
Instantiations	3,764,726	4,689,515	924,789
Memory used	250,948K	271,278K	20,330K
Memory allocs	10,583,093	12,346,467	1,763,374
Parse time	0.071s	0.073s	0.002s
Bind time	0.027s	0.027s	0s
Check time	1.542s	1.847s	0.305s
Emit time	0s	0s	0s
Total time	1.65s	1.956s	0.306s

---

Reported by octocov

[github-actions[bot]]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	36,096.72	48,929.37	31,741.98	27,618.82
hono (current)	bun	35,610.19	47,537.32	31,717.07	27,576.19
Change		-1.35%	-2.85%	-0.08%	-0.15%

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 91.52%. Comparing base (a5f3958) to head (51765d1). :warning: Report is 25 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4529   +/-   ##
=======================================
  Coverage   91.52%   91.52%           
=======================================
  Files         172      172           
  Lines       11221    11221           
  Branches     3254     3254           
=======================================
  Hits        10270    10270           
  Misses        950      950           
  Partials        1        1           

:umbrella: View full report in Codecov by Sentry.
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[github-actions[bot]]

Bundle size check

	main (342ff3b)	#4529 (4bffc55)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (342ff3b)	#4529 (4bffc55)	+/-
Files	303	303	0
Lines	140,900	140,950	50
Identifiers	128,526	128,577	51
Symbols	269,140	289,611	20,471
Types	198,856	203,450	4,594
Instantiations	639,355	1,039,267	399,912
Memory used	371,793K	396,776K	24,983K
I/O read	0.04s	0.02s	-0.02s
I/O write	0s	0s	0s
Parse time	0.74s	0.73s	-0.01s
Bind time	0.3s	0.3s	0s
Check time	2.83s	3.73s	0.9s
Emit time	0s	0s	0s
Total time	3.87s	4.76s	0.89s

Compiler Diagnostics (typescript-go)

	main (342ff3b)	#4529 (4bffc55)	+/-
Files	272	272	0
Lines	118,789	118,839	50
Identifiers	117,959	118,010	51
Symbols	378,470	419,388	40,918
Types	360,479	369,694	9,215
Instantiations	3,764,726	4,686,990	922,264
Memory used	250,948K	270,666K	19,718K
Memory allocs	10,583,093	12,329,606	1,746,513
Parse time	0.071s	0.102s	0.031s
Bind time	0.027s	0.047s	0.02s
Check time	1.542s	2.023s	0.481s
Emit time	0s	0s	0s
Total time	1.65s	2.179s	0.529s

---

Reported by octocov

[github-actions[bot]]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	36,578.76	50,306.13	31,365.39	28,064.75
hono (current)	bun	37,618.29	50,918.75	33,757.68	28,178.45
Change		+2.84%	+1.22%	+7.63%	+0.41%

[github-actions[bot]]

Bundle size check

	main (342ff3b)	#4529 (07bd6c3)	+/-
Bundle Size (B)	18,363B	18,363B	0B
Bundle Size (KB)	17.93K	17.93K	0K

Compiler Diagnostics (tsc)

	main (342ff3b)	#4529 (07bd6c3)	+/-
Files	303	303	0
Lines	140,900	140,948	48
Identifiers	128,526	128,576	50
Symbols	269,140	289,624	20,484
Types	198,856	201,122	2,266
Instantiations	639,355	1,030,892	391,537
Memory used	371,793K	391,504K	19,711K
I/O read	0.04s	0.03s	-0.01s
I/O write	0s	0s	0s
Parse time	0.74s	0.82s	0.08s
Bind time	0.3s	0.36s	0.06s
Check time	2.83s	3.79s	0.96s
Emit time	0s	0s	0s
Total time	3.87s	4.97s	1.1s

Compiler Diagnostics (typescript-go)

	main (342ff3b)	#4529 (07bd6c3)	+/-
Files	272	272	0
Lines	118,789	118,837	48
Identifiers	117,959	118,009	50
Symbols	378,470	419,422	40,952
Types	360,479	365,724	5,245
Instantiations	3,764,726	4,672,600	907,874
Memory used	250,948K	269,780K	18,832K
Memory allocs	10,583,093	12,295,305	1,712,212
Parse time	0.071s	0.081s	0.01s
Bind time	0.027s	0.016s	-0.011s
Check time	1.542s	1.702s	0.16s
Emit time	0s	0s	0s
Total time	1.65s	1.801s	0.151s

---

Reported by octocov

[github-actions[bot]]

HTTP Performance Benchmark

Framework	Runtime	Average	Ping	Query	Body
hono (origin/main)	bun	37,708.95	52,921.71	33,584.66	26,620.48
hono (current)	bun	37,455.66	51,865.85	33,761.57	26,739.56
Change		-0.67%	-2.00%	+0.53%	+0.45%

[yusukebe]

The issue was resolved by https://github.com/honojs/hono/pull/4552. Closing.