Tilt watches files which should be ignored

Steps to Reproduce

Using:

• Tilt v0.23.2
• macOS v12.0.1
• Docker Desktop v4.3.0
• Kubernetes v1.22.4
• Apple M1 Pro

Demonstration using https://github.com/tilt-dev/ignore-examples:

git clone https://github.com/tilt-dev/ignore-examples
cd ignore-examples
tilt up

Then edit service-a/ignored-by-tiltignore.txt.

Expected Behavior

service-a does not rebuild after editing the file.

Current Behavior

service-a rebuilds:

$ tilt get filewatches
NAME                              CREATED AT
configs:(Tiltfile)                2021-12-10T18:02:55Z
image:ignore-examples-service-a   2021-12-10T18:02:55Z
image:ignore-examples-service-b   2021-12-10T18:02:55Z

$ tilt get filewatches image:ignore-examples-service-a -o yaml
apiVersion: tilt.dev/v1alpha1
kind: FileWatch
metadata:
  annotations:
    tilt.dev/resource: ignore-examples-service-a
    tilt.dev/target-id: image:ignore-examples-service-a
  creationTimestamp: "2021-12-10T18:02:55Z"
  name: image:ignore-examples-service-a
  ownerReferences:
  - apiVersion: tilt.dev/v1alpha1
    blockOwnerDeletion: true
    controller: true
    kind: Tiltfile
    name: (Tiltfile)
    uid: 868df0fa-e7ec-457d-b6cc-78cb7c8d2bed
  resourceVersion: "13"
  uid: f1d700dd-cd08-4f8f-8219-476d0a5028af
spec:
  disableSource:
    configMap:
      key: isDisabled
      name: ignore-examples-service-a-disable
  ignores:
  - basePath: /Users/spencerelliott/dev/tilt-dev/ignore-examples/Tiltfile
  - basePath: /Users/spencerelliott/dev/tilt-dev/ignore-examples/service-a
    patterns:
    - ignored-by-docker-build-ignore.txt
  - basePath: /Users/spencerelliott/dev/tilt-dev/ignore-examples/service-a
    patterns:
    - ignored-by-dockerignore.txt
  - basePath: /Users/spencerelliott/dev/tilt-dev/ignore-examples
    patterns:
    - '*/ignored-by-tiltignore.txt'
  watchedPaths:
  - /Users/spencerelliott/dev/tilt-dev/ignore-examples/service-a
status:
  disableStatus:
    disabled: false
    lastUpdateTime: "2021-12-10T18:04:00Z"
    reason: ConfigMap/key "ignore-examples-service-a-disable"/"isDisabled" is false
  fileEvents:
  - seenFiles:
    - /Users/spencerelliott/Dev/tilt-dev/ignore-examples/service-a/not-ignored.txt
    - /Users/spencerelliott/Dev/tilt-dev/ignore-examples/service-a/not-ignored.txt
    time: "2021-12-10T18:03:37.169397Z"
  - seenFiles:
    - /Users/spencerelliott/Dev/tilt-dev/ignore-examples/service-a/ignored-by-tiltignore.txt
    - /Users/spencerelliott/Dev/tilt-dev/ignore-examples/service-a/ignored-by-tiltignore.txt
    time: "2021-12-10T18:04:00.568557Z"
  lastEventTime: "2021-12-10T18:04:00.568557Z"
  monitorStartTime: "2021-12-10T18:02:55.686026Z"

Context

tilt doctor Output

$ tilt doctor
Tilt: v0.23.2, built 2021-12-03
System: darwin-arm64
---
Docker
- Host: [default]
- Server Version: 20.10.11
- API Version: 1.41
- Builder: 2
- Compose Version: v1.29.2 (build 5becea4c)
---
Kubernetes
- Env: docker-for-desktop
- Context: docker-desktop
- Cluster Name: docker-desktop
- Namespace: default
- Container Runtime: docker
- Version: v1.22.4
- Cluster Local Registry: none
---
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About Your Use Case

This is a minimal repro of a problem which is affecting our main repo, which contains Kubernetes host path volumes in a directory (repo)/volumes. These files are configured to be ignored by Git, Docker, and Tilt, but Tilt is watching the files and triggering unnecessary rebuilds, causing errors and slowing down our development.

Start by reproducing the issue with the tilt-dev/ignore-examples repository, then inspect the FileWatch output from tilt get filewatches image:ignore-examples-service-a -o yaml. Done means editing service-a/ignored-by-tiltignore.txt no longer rebuilds service-a while non-ignored changes still trigger the expected rebuild.