pub upgrade crash on dead loop instead of showing the problem

[DartBot]

<img src="https://avatars.githubusercontent.com/u/2742173?v=3" align="left" width="96" height="96"hspace="10"> Issue by rinick
Originally opened as dart-lang/sdk#22903

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pub upgrade fails when I start to use the args 1.3 package

when I run "pub upgrade -v"
it shows a dead loop like this

selection path 1.0.0 from hosted does not match >=1.2.0 <2.0.0
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
backjump to yaml
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select y
aml 2.1.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=0.13.0 <0.15.3 pub dependency on barback
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=1.0.0 <2.0.0 pub dependency on source_span
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=0.9.1 <2.0.0 pub dependency on stack_trace
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select
 matcher 0.11.4+3 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * sele
ct petitparser 1.3.7 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * se
lect pool 1.0.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | *
select collection 1.1.0 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
selection path 1.0.0 from hosted does not match >=1.2.0 <2.0.0
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
backjump to code_transformers
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select cod
e_transformers 0.0.1-dev.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add implic
it >=0.13.0 <0.15.3 pub dependency on barback
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add implic
it >=1.0.0 <2.0.0 pub dependency on source_span
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add implic
it >=0.9.1 <2.0.0 pub dependency on stack_trace
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select y
aml 2.1.2 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select
 matcher 0.11.4+3 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * sele
ct petitparser 1.3.7 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * se
lect pool 1.0.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | *
select collection 1.1.0 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
selection path 1.0.0 from hosted does not match >=1.2.0 <2.0.0
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
backjump to yaml
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select y
aml 2.1.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=0.13.0 <0.15.3 pub dependency on barback
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=1.0.0 <2.0.0 pub dependency on source_span
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | add impl
icit >=0.9.1 <2.0.0 pub dependency on stack_trace
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select
 matcher 0.11.4+3 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * sele
ct petitparser 1.3.7 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * se
lect pool 1.0.1 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | *
select collection 1.1.0 from hosted
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
selection path 1.0.0 from hosted does not match >=1.2.0 <2.0.0
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
backjump to code_transformers
SLVR: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * select cod
e_transformers 0.0.1-dev from hosted

[DartBot]

<img src="https://avatars.githubusercontent.com/u/2108507?v=3" align="left" width="48" height="48"hspace="10"> Comment by dgrove

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Added Area-Pub, Triaged labels.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/188?v=3" align="left" width="48" height="48"hspace="10"> Comment by nex3

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I assume this is issue #912, but it's hard to know without more detail. The log output you posted, in addition to being difficult to read due to line wrapping, doesn't actually contain any error messages—it's just various package versions being selected and unselected.

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Added NeedsInfo label.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/2742173?v=3" align="left" width="48" height="48"hspace="10"> Comment by rinick

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as you can see it's a dead loop, the console just prints these things forever.

but after updating to 1.9.0dev10.13, I can no longer reproduce this issue. maybe the dependency loop in those pub packages was fixed by package owner.

[DartBot]

<img src="https://avatars.githubusercontent.com/u/188?v=3" align="left" width="48" height="48"hspace="10"> Comment by nex3

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It's not actually infinite; if you look closely you'll see that the versions being selected vary over time. Unfortunately it is exponential, which is an unfortunate necessity for backtracking version resolution.

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Added Duplicate label.
Marked as being merged into #912.