ensure no previous expression as well (#2320)

NEWS.md

@@ -8,6 +8,9 @@
 
 ### Lint accuracy fixes: removing false positives
 * `unreachable_code_linter()` ignores reachable code in inline functions like `function(x) if (x > 2) stop() else x` (#2259, @MEO265).
+* `unnecessary_lambda_linter()`
+  + ignores extractions with explicit returns like `lapply(l, function(x) foo(x)$bar)` (#2258, @MichaelChirico).
+  + ignores calls on the RHS of operators like `lapply(l, function(x) "a" %in% names(x))` (#2310, @MichaelChirico).
 
 # lintr 3.1.1
 

R/unnecessary_lambda_linter.R

@@ -76,6 +76,10 @@ unnecessary_lambda_linter <- function() {
           position() = 2
           and preceding-sibling::expr/SYMBOL_FUNCTION_CALL
           and not(preceding-sibling::*[1][self::EQ_SUB])
+          and not(parent::expr[
+            preceding-sibling::expr[not(SYMBOL_FUNCTION_CALL)]
+            or following-sibling::*[not(self::OP-RIGHT-PAREN or self::OP-RIGHT-BRACE)]
+          ])
         ]/SYMBOL
       and count(OP-LEFT-PAREN) + count(OP-LEFT-BRACE/following-sibling::expr/OP-LEFT-PAREN) = 1
     ]

tests/testthat/test-unnecessary_lambda_linter.R

@@ -65,6 +65,10 @@ test_that("unnecessary_lambda_linter skips allowed usages", {
     NULL,
     linter
   )
+
+  # only call is on RHS of operator, #2310
+  expect_lint("lapply(l, function(x) 'a' %in% names(x))", NULL, linter)
+  expect_lint("lapply(l, function(x = 1) 'a' %in% names(x))", NULL, linter)
 })
 
 test_that("unnecessary_lambda_linter blocks simple disallowed usage", {