Cap Format-Nicely2 recursion depth to avoid call depth overflow#2830
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Failing asserts format the actual value with Format-Nicely2, which recurses through every property and collection element. Deeply nested or self-referential objects (such as SMO stub types, or DirectoryInfo whose Parent/Root point back up the tree) recursed until PowerShell threw "The script failed due to call depth overflow", which hid the real assertion result. Thread a Depth counter through the recursive formatters (Format-Collection2/Object2/Hashtable2/Dictionary2 and Format-Nicely2) and stop expanding once past a fixed depth, printing the value's type instead. Scalars are still fully formatted; only the recursing container/object branches are guarded. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Problem
When an assertion fails, Pester formats the actual value for the error message with
Format-Nicely2(src/Format2.ps1).Format-Nicely2→Format-Object2recurses through every property of an object by callingFormat-Nicely2again per property (and likewiseFormat-Collection2/Format-Hashtable2/Format-Dictionary2per element).For deeply nested or self-referential objects this recurses until PowerShell throws:
which hides the real assertion result. This happens with SQL Server Management Objects (SMO) stub types (reported in #2828) and, previously, with
DirectoryInfowhoseParent/Rootpoint back up the tree (#2474, partially mitigated by a hard-coded property map).Fix
Thread an
[int]$Depthparameter through the four recursive formatters andFormat-Nicely2. Each recursive call increments the depth; once past a fixed maximum depth of10Format-Nicely2stops expanding and prints the value's short type instead (e.g.[PSObject]), which is enough for a diagnostic message and cannot recurse further. The limit is a hard-coded constant, not a configurable script variable.The guard sits after the scalar branches (null/bool/string/type/number/scriptblock, which never recurse) and before the container/object branches (which do), so simple values are always fully formatted. Behavior for normally‑nested values is unchanged — the depth default of
0makes every existing single‑level call identical to before.Example, before vs after, for a self‑referential object:
The script failed due to call depth overflow.Expected value to have type [string], but got [PSObject] PSObject{Name='x'; Self=PSObject{…; Self=[PSObject]}}.Tests
tst/Format2.Tests.ps1: a self-referential object is truncated with a type marker instead of overflowing; values nested past the max depth are cut off.tst/functions/assert/General/Should-HaveType.Tests.ps1: a self-referential actual value now yields a normal assertion failure rather than a call-depth overflow.989 assert/format tests pass; the custom build analyzer is clean on the changed file.
Fix #2828