tests/tinytest/test-traversal.R

In astgrepr: Parse and Manipulate R Code

source("helpers.R")
using("astgrepr")

### get the previous/next node ---------------------------

src <- "
print('hi there')
a <- 1
fn <- function(x) {
  x + 1
}
"
root <- src |>
  tree_new() |>
  tree_root()

expect_snapshot(
  label = "previous_node",
  root |>
    node_find(ast_rule(pattern = "a <- $A")) |>
    node_prev() |>
    node_text()
)

expect_snapshot(
  label = "next_node",
  root |>
    node_find(ast_rule(pattern = "a <- $A")) |>
    node_next() |>
    node_text()
)

expect_snapshot(
  label = "next_all_nodes",
  root |>
    node_find(ast_rule(pattern = "a <- $A")) |>
    node_next_all() |>
    node_text_all()
)

### get the parent/child node ---------------------------

src <- "
print('hi there')
a <- 1
fn <- function(x) {
  x + 1
}
"
root <- src |>
  tree_new() |>
  tree_root()

expect_snapshot(
  label = "parent_node",
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_parent() |>
    node_text()
)

expect_snapshot(
  label = "ancestors_node",
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_ancestors() |>
    node_text_all()
)

expect_snapshot(
  label = "child_node",
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_child(0) |>
    node_text()
)

expect_equal(
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_child(10) |>
    node_text(),
  list(rule_1 = NULL)
)

expect_error(
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_child(1.5),
  "`nth` must be an integer of length 1."
)

expect_error(
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_child("a"),
  "`nth` must be an integer of length 1."
)

expect_error(
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_child(1:2),
  "`nth` must be an integer of length 1."
)

expect_snapshot(
  label = "children_node",
  root |>
    node_find(ast_rule(pattern = "$VAR + 1")) |>
    node_children() |>
    node_text_all()
)