fix: ensure progress bars display consistently across all environments (#8411)

The progress configuration's default value and runtime behavior now use
identical logic, preventing cases where progress bars were unexpectedly
disabled in cloud IDEs and other environments.

Fixes npm/statusboard#996

Author: owlstronaut

tap-snapshots/test/lib/docs.js.test.cjs

@@ -1290,7 +1290,8 @@ a semver. Like the \`rc\` in \`1.2.0-rc.8\`.
 
 #### \`progress\`
 
-* Default: \`true\` unless running in a known CI system
+* Default: \`true\` when not in CI and both stderr and stdout are TTYs and not
+  in a dumb terminal
 * Type: Boolean
 
 When set to \`true\`, npm will display a progress bar during time intensive

workspaces/config/lib/definitions/definitions.js

@@ -1571,9 +1571,9 @@ const definitions = {
     },
   }),
   progress: new Definition('progress', {
-    default: !ciInfo.isCI,
+    default: !(ciInfo.isCI || !process.stderr.isTTY || !process.stdout.isTTY || process.env.TERM === 'dumb'),
     defaultDescription: `
-      \`true\` unless running in a known CI system
+      \`true\` when not in CI and both stderr and stdout are TTYs and not in a dumb terminal
     `,
     type: Boolean,
     description: `
@@ -1583,11 +1583,8 @@ const definitions = {
       Set to \`false\` to suppress the progress bar.
     `,
     flatten (key, obj, flatOptions) {
-      flatOptions.progress = !obj.progress ? false
-        // progress is only written to stderr but we disable it unless stdout is a tty
-        // also. This prevents the progress from appearing when piping output to another
-        // command which doesn't break anything, but does look very odd to users.
-        : !!process.stderr.isTTY && !!process.stdout.isTTY && process.env.TERM !== 'dumb'
+      // Only show progress if explicitly enabled AND we have proper TTY environment
+      flatOptions.progress = !!obj.progress && !!process.stderr.isTTY && !!process.stdout.isTTY && process.env.TERM !== 'dumb'
     },
   }),
   provenance: new Definition('provenance', {

workspaces/config/test/definitions/definitions.js

@@ -402,6 +402,7 @@ t.test('progress', t => {
 
   const flat = {}
 
+  // Test flatten function behavior
   mockDefs().progress.flatten('progress', {}, flat)
   t.strictSame(flat, { progress: false })
 
@@ -417,6 +418,59 @@ t.test('progress', t => {
   mockDefs().progress.flatten('progress', { progress: true }, flat)
   t.strictSame(flat, { progress: false })
 
+  // Ensures consistency between default and flatOptions behavior
+  t.test('default value consistency', t => {
+    // Test case 1: Both TTYs, normal terminal, not CI
+    setEnv({ tty: true, term: 'xterm' })
+    const def1 = mockDefs({ 'ci-info': { isCI: false, name: null } }).progress
+    t.equal(def1.default, true, 'default should be true when both TTYs, normal terminal, and not CI')
+
+    // Test case 2: No TTYs, not CI
+    setEnv({ tty: false, term: 'xterm' })
+    const def2 = mockDefs({ 'ci-info': { isCI: false, name: null } }).progress
+    t.equal(def2.default, false, 'default should be false when no TTYs')
+
+    // Test case 3: Both TTYs but dumb terminal, not CI
+    setEnv({ tty: true, term: 'dumb' })
+    const def3 = mockDefs({ 'ci-info': { isCI: false, name: null } }).progress
+    t.equal(def3.default, false, 'default should be false in dumb terminal')
+
+    // Test case 4: Mixed TTY states, not CI
+    mockGlobals(t, {
+      'process.stderr.isTTY': true,
+      'process.stdout.isTTY': false,
+      'process.env.TERM': 'xterm',
+    })
+    const def4 = mockDefs({ 'ci-info': { isCI: false, name: null } }).progress
+    t.equal(def4.default, false, 'default should be false when only one TTY')
+
+    // Test case 5: Good TTY environment but in CI
+    setEnv({ tty: true, term: 'xterm' })
+    const def5 = mockDefs({ 'ci-info': { isCI: true, name: 'github-actions' } }).progress
+    t.equal(def5.default, false, 'default should be false in CI even with good TTY environment')
+
+    t.end()
+  })
+
+  // Test that flatten behavior is independent of CI detection
+  t.test('flatten function ignores CI detection', t => {
+    const flatObj = {}
+
+    // Test that CI doesn't affect flatten behavior when user explicitly enables
+    setEnv({ tty: true, term: 'xterm' })
+    const defsCI = mockDefs({ 'ci-info': { isCI: true, name: 'github-actions' } })
+    defsCI.progress.flatten('progress', { progress: true }, flatObj)
+    t.equal(flatObj.progress, true, 'flatten should enable progress in CI if user explicitly sets true and TTY is available')
+
+    // Test that non-CI doesn't guarantee flatten success if TTY is bad
+    setEnv({ tty: false, term: 'xterm' })
+    const defsNoCI = mockDefs({ 'ci-info': { isCI: false, name: null } })
+    defsNoCI.progress.flatten('progress', { progress: true }, flatObj)
+    t.equal(flatObj.progress, false, 'flatten should disable progress outside CI if TTY is not available')
+
+    t.end()
+  })
+
   t.end()
 })