Error: Dictionary changed size during iteration

Describe the bug

I’ve encountered this error twice so far in two days, coincidentally(?) since I upgraded to 0.14.1, and saw it on dbt Cloud. The error is: Completed with 1 error and 0 warnings: dictionary changed size during iteration In both cases this happened when doing dbt test --models source:* (Reference: runs #1683050 and #1678913 in dbt Cloud)

Screenshots and log output

Backtrace: Traceback (most recent call last): File “/usr/local/lib/python3.6/dist-packages/dbt/node_runners.py”, line 196, in safe_run result = self.compile_and_execute(manifest, ctx) File “/usr/local/lib/python3.6/dist-packages/dbt/node_runners.py”, line 134, in compile_and_execute ctx.node = self.compile(manifest) File “/usr/local/lib/python3.6/dist-packages/dbt/node_runners.py”, line 300, in compile return compile_node(self.adapter, self.config, self.node, manifest, {}) File “/usr/local/lib/python3.6/dist-packages/dbt/compilation.py”, line 221, in compile_node node = compiler.compile_node(node, manifest, extra_context) File “/usr/local/lib/python3.6/dist-packages/dbt/compilation.py”, line 118, in compile_node compiled_node, self.config, manifest) File “/usr/local/lib/python3.6/dist-packages/dbt/context/runtime.py”, line 150, in generate model, runtime_config, manifest, None, Provider()) File “/usr/local/lib/python3.6/dist-packages/dbt/context/common.py”, line 496, in generate return generate_model(model, config, manifest, source_config, provider) File “/usr/local/lib/python3.6/dist-packages/dbt/context/common.py”, line 471, in generate_model source_config, provider) File “/usr/local/lib/python3.6/dist-packages/dbt/context/common.py”, line 408, in generate_base “graph”: manifest.to_flat_graph(), File “/usr/local/lib/python3.6/dist-packages/dbt/contracts/graph/manifest.py”, line 235, in to_flat_graph k: v.serialize() for k, v in self.nodes.items() File “/usr/local/lib/python3.6/dist-packages/dbt/contracts/graph/manifest.py”, line 235, in <dictcomp> k: v.serialize() for k, v in self.nodes.items() File “/usr/local/lib/python3.6/dist-packages/dbt/api/object.py”, line 63, in serialize return copy.deepcopy(self._contents) File “/usr/lib/python3.6/copy.py”, line 150, in deepcopy y = copier(x, memo) File “/usr/lib/python3.6/copy.py”, line 239, in _deepcopy_dict for key, value in x.items(): RuntimeError: dictionary changed size during iteration

System information

Which database are you using dbt with?

• postgres
• redshift
• bigquery
• snowflake
• other (specify: ____________)

The output of dbt --version:

installed version: 0.14.1
   latest version: 0.14.1

The operating system you’re using: The error occured on dbt Cloud

The output of python --version:

Additional context

Add any other context about the problem here.

[drewbanin]

This was fixed in https://github.com/fishtown-analytics/dbt/pull/1750

We’re going to cut an 0.14.3 release which includes this fix next week!

[MartinGuindon]

@drewbanin To my knowledge, I’ve actually never encountered that isssue before upgrading to 0.14.1. Also I’ve had quite a few occurrences in the last 2 days.

Runs #1698615, #1696637, #1696312, #1693258, #1692100, #1691359, #1687687, #1687106, #1686503… and maybe more, I stopped looking after page 2.