Fix matched := when using 'allow_equal_assign'

r-lib · Sep 29, 2024 · a4fb906 · a4fb906
1 parent 445f40f
commit a4fb906
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Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/R/assignment_linter.R b/R/assignment_linter.R
@@ -91,7 +91,7 @@ assignment_linter <- function(allow_cascading_assign = TRUE,
 
  xpath <- paste(collapse = " | ", c(
  # always block = (NB: the parser differentiates EQ_ASSIGN, EQ_SUB, and EQ_FORMALS)
- if (allow_equal_assign) "//LEFT_ASSIGN" else "//EQ_ASSIGN",
+ if (allow_equal_assign) "//LEFT_ASSIGN[text() = '<-']" else "//EQ_ASSIGN",
  # -> and ->> are both 'RIGHT_ASSIGN'
  if (!allow_right_assign) "//RIGHT_ASSIGN" else if (!allow_cascading_assign) "//RIGHT_ASSIGN[text() = '->>']",
  # <-, :=, and <<- are all 'LEFT_ASSIGN'; check the text if blocking <<-.

diff --git a/tests/testthat/test-assignment_linter.R b/tests/testthat/test-assignment_linter.R
@@ -199,4 +199,7 @@ test_that("= instead of <- can be used for assignment", {
 
  expect_lint("blah = 1", NULL, linter)
  expect_lint("blah <- 1", lint_msg, linter)
+
+ # data.table's left assign := needs to be silent
+ expect_lint("dt[, x := 42]", NULL, linter)
 })