feat: do not log secret variables (#2514)

testdata/secrets/Taskfile.yml

@@ -0,0 +1,83 @@
+version: '3'
+
+vars:
+  # Public variable
+  APP_NAME: myapp
+
+  # Secret variable with value
+  API_KEY:
+    value: "secret-api-key-123"
+    secret: true
+
+  # Secret variable from shell command
+  PASSWORD:
+    sh: "echo 'my-super-secret-password'"
+    secret: true
+
+  # Non-secret variable
+  PUBLIC_URL: https://example.com
+
+tasks:
+  test-secret-masking:
+    desc: Test that secret variables are masked in logs
+    cmds:
+      - echo "Deploying {{.APP_NAME}} to {{.PUBLIC_URL}}"
+      - echo "Using API key {{.API_KEY}}"
+      - echo "Password is {{.PASSWORD}}"
+      - echo "Public app name is {{.APP_NAME}}"
+
+  test-multiple-secrets:
+    desc: Test multiple secrets in one command
+    cmds:
+      - echo "API={{.API_KEY}} PWD={{.PASSWORD}}"
+
+  test-mixed:
+    desc: Test mix of secret and public vars
+    vars:
+      LOCAL_SECRET:
+        value: "task-level-secret"
+        secret: true
+    cmds:
+      - echo "App={{.APP_NAME}} Secret={{.LOCAL_SECRET}} URL={{.PUBLIC_URL}}"
+
+  test-deferred-secret:
+    desc: Test that deferred commands mask secrets
+    vars:
+      DEFERRED_SECRET:
+        value: "deferred-secret-value"
+        secret: true
+    cmds:
+      - echo "Starting task"
+      - defer: echo "Cleanup with secret={{.DEFERRED_SECRET}} and app={{.APP_NAME}}"
+      - echo "Main command executed"
+
+  test-dynamic-secret-verbose:
+    desc: Test that dynamic (sh) secrets are masked even in verbose logs
+    cmds:
+      - echo "Password is {{.PASSWORD}}"
+
+  test-secret-key-order:
+    desc: Test that "secret" may be declared before the value/sh key
+    vars:
+      SECRET_FIRST:
+        secret: true
+        value: "order-independent-secret"
+      SH_SECRET_FIRST:
+        secret: true
+        sh: "echo 'sh-order-independent-secret'"
+    cmds:
+      - echo "Value={{.SECRET_FIRST}} Sh={{.SH_SECRET_FIRST}}"
+
+  test-env-secret-limitation:
+    desc: Test showing that env vars with secret flag are NOT masked (limitation)
+    env:
+      SECRET_TOKEN:
+        value: "env-secret-token-123"
+        secret: true
+      PUBLIC_ENV: "public-value"
+    cmds:
+      # Templates {{.VAR}} don't work with env - they're empty
+      - echo "Token via template is {{.SECRET_TOKEN}}"
+      # Shell $VAR works but is NOT masked (env vars not in template system)
+      - echo "Token via shell is $SECRET_TOKEN"
+      - echo "Public env is {{.PUBLIC_ENV}}"