Display fails with only one sample

[LilithHafner]

I ran into this issue when benchmarking a long running function in the REPL where display is automatic:

julia> @benchmark long_running()

It can be easily replicated with

@benchmark sleep(5)

or

@benchmark 1+1 samples=1

To get a nicer error message, I displayed explicitly with this:

julia> display(@benchmark sleep(5))
BechmarkTools.Trial: 1 samples with 1 evaluations.
 Range (min … max):  5.004 s … 5.004 s  ┊ GC (min … max): 0.00% … 0.00%
 Time  (median):     5.004 s            ┊ GC (median):    0.00%
 Time  (mean ± σ):   5.004 s ±   NaN s  ┊ GC (mean ± σ):  0.00% ±  NaN%ERROR: BoundsError: attempt to access 1-element Vector{Float64} at index [0]
Stacktrace:
 [1] getindex
   @ ./array.jl:801 [inlined]
 [2] show(io::IOContext{Base.TTY}, #unused#::MIME{Symbol("text/plain")}, t::BenchmarkTools.Trial)
   @ BenchmarkTools ~/.julia/packages/BenchmarkTools/Rqvks/src/trials.jl:441
 [3] (::REPL.var"#38#39"{REPL.REPLDisplay{REPL.LineEditREPL}, MIME{Symbol("text/plain")}, Base.RefValue{Any}})(io::Any)
   @ REPL /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:220
 [4] with_repl_linfo(f::Any, repl::REPL.LineEditREPL)
   @ REPL /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:462
 [5] display(d::REPL.REPLDisplay, mime::MIME{Symbol("text/plain")}, x::Any)
   @ REPL /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:213
 [6] display(d::REPL.REPLDisplay, x::Any)
   @ REPL /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:225
 [7] display(x::Any)
   @ Base.Multimedia ./multimedia.jl:328
 [8] top-level scope
   @ ~/.julia/packages/BenchmarkTools/Rqvks/src/execution.jl:389

I'd rather get this:

julia> display(@benchmark sleep(5))
BechmarkTools.Trial: 1 samples with 1 evaluations.
 Range (min … max):  5.004 s … 5.004 s  ┊ GC (min … max): 0.00% … 0.00%
 Time  (median):     5.004 s            ┊ GC (median):    0.00%
 Time  (mean ± σ):   5.004 s ±   NaN s  ┊ GC (mean ± σ):  0.00% ±  NaN%

[LilithHafner]

On BenchmarkTools v1.3.1

julia> @benchmark sleep(5)
BenchmarkTools.Trial: 1 sample with 1 evaluation.
 Single result which took 5.002 s (0.00% GC) to evaluate,
 with a memory estimate of 144 bytes, over 5 allocations.