From 588e2394c60dbf72624fba5990dfe34a62893de9 Mon Sep 17 00:00:00 2001
From: Gauarv Chaudhary <chaudharygaurav2004@gmail.com>
Date: Fri, 12 Dec 2025 22:05:22 +0530
Subject: [PATCH 1/3] test: add failing test for multiple colliders bug (#878)

Reproduces the error when check_dag encounters multiple colliders
in adjustment nodes, causing: 'length = 2' in coercion to 'logical(1)'

The test currently fails as expected and will pass once the bug
is fixed in the .finalize_dag() function.

Issue: #878
---
 tests/testthat/test-check_dag.R | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/tests/testthat/test-check_dag.R b/tests/testthat/test-check_dag.R
index a25d2ff1f..b840a37ae 100644
--- a/tests/testthat/test-check_dag.R
+++ b/tests/testthat/test-check_dag.R
@@ -201,3 +201,21 @@ test_that("check_dag, formula-interface", {
   )
   expect_identical(dag, dag2)
 })
+
+
+test_that("check_dag handles multiple colliders correctly - issue #878", {
+  # This test reproduces the error from issue #878
+  # The DAG has multiple colliders (both 'a' and 'b' are colliders)
+  # because they both have multiple incoming paths from 'c' and 'd'
+  expect_error(
+    check_dag(
+      y ~ x + a + b,
+      a ~ c + d,
+      b ~ c + d,
+      outcome = "y",
+      exposure = "x",
+      adjusted = ~ a + b
+    ),
+    regexp = "length = 2.*coercion to.*logical\\(1\\)"
+  )
+})

From 3b0421220c0030fb4d934527e8a41c4fd8507300 Mon Sep 17 00:00:00 2001
From: Gauarv Chaudhary <chaudharygaurav2004@gmail.com>
Date: Fri, 12 Dec 2025 22:16:25 +0530
Subject: [PATCH 2/3] fix: use expect_no_error for proper regression test

Changed from expect_error to expect_no_error so the test:
- FAILS now (while bug exists)
- PASSES after the fix is applied

Issue: #878
---
 tests/testthat/test-check_dag.R | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tests/testthat/test-check_dag.R b/tests/testthat/test-check_dag.R
index b840a37ae..4414635c2 100644
--- a/tests/testthat/test-check_dag.R
+++ b/tests/testthat/test-check_dag.R
@@ -207,7 +207,8 @@ test_that("check_dag handles multiple colliders correctly - issue #878", {
   # This test reproduces the error from issue #878
   # The DAG has multiple colliders (both 'a' and 'b' are colliders)
   # because they both have multiple incoming paths from 'c' and 'd'
-  expect_error(
+  # This test FAILS while bug exists, PASSES after fix
+  expect_no_error(
     check_dag(
       y ~ x + a + b,
       a ~ c + d,
@@ -215,7 +216,6 @@ test_that("check_dag handles multiple colliders correctly - issue #878", {
       outcome = "y",
       exposure = "x",
       adjusted = ~ a + b
-    ),
-    regexp = "length = 2.*coercion to.*logical\\(1\\)"
+    )
   )
 })

From de2839fa431d8ebd63bf18264e2b02d6c5923cb2 Mon Sep 17 00:00:00 2001
From: Gauarv Chaudhary <chaudharygaurav2004@gmail.com>
Date: Sat, 13 Dec 2025 12:58:27 +0530
Subject: [PATCH 3/3] fix: handle multiple colliders in check_dag (#878)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix error when check_dag encounters multiple colliders in adjustment
nodes. The issue was that 'collider %in% adjustment_nodes' returns a
vector of logical values when there are multiple colliders, which
cannot be used with the && operator.

Solution: Use any() to properly handle vector comparison.

Also add missing author names to WORDLIST for spell check:
- Dunkler, Graham, Gregorich, Morrissey, Papeş, Pandey, Park,
  Ruxton, Strohmaier

Fixes #878
---
 R/check_dag.R | 2 +-
 inst/WORDLIST | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/R/check_dag.R b/R/check_dag.R
index cc5acfea7..dca48df3f 100644
--- a/R/check_dag.R
+++ b/R/check_dag.R
@@ -347,7 +347,7 @@ check_dag <- function(
       # - required is NULL and current adjustment not NULL
       # - OR we have a collider in current adjustments
       incorrectly_adjusted = (is.null(adjustment_set) && !is.null(adjustment_nodes)) ||
-        (!is.null(collider) && collider %in% adjustment_nodes), # nolint
+        (!is.null(collider) && any(collider %in% adjustment_nodes)), # nolint
       current_adjustments = adjustment_nodes,
       minimal_adjustments = minimal_adjustments,
       collider = collider
diff --git a/inst/WORDLIST b/inst/WORDLIST
index d9394796d..847ab8bbe 100644
--- a/inst/WORDLIST
+++ b/inst/WORDLIST
@@ -62,6 +62,7 @@ Dominicy
 Dordrecht
 Dorie
 Dunson
+Dunkler
 Durbin
 Dxy
 Döring
@@ -88,6 +89,8 @@ Gabry
 Gazen
 Gelman
 Gnanadesikan
+Graham
+Gregorich
 Guilford
 Hartig
 HDI
@@ -158,6 +161,7 @@ Michalos
 Moosbrugger
 Monette
 Mora
+Morrissey
 Multicollinearity
 MuMIn
 NFI
@@ -178,6 +182,9 @@ OSF
 OSX
 Olkin
 PNFI
+Papeş
+Pandey
+Park
 Pek
 Petrov
 polychoric
@@ -202,6 +209,7 @@ Rousseeuw
 Routledge
 Rouder
 Rouder's
+Ruxton
 SEM
 SRMR
 Scheepers
@@ -220,6 +228,7 @@ Specifity
 Sphericity
 Springer
 Stata
+Strohmaier
 Subscales
 TLI
 Technometrics