From 52642ccc4b0882ef8e4c5d9dd1ccbb23040c193e Mon Sep 17 00:00:00 2001
From: yjunechoe <jchoe001@gmail.com>
Date: Sat, 15 Feb 2025 16:13:52 -0500
Subject: [PATCH 1/4] more helpful error messages when yaml-writing with
 non-lazy tbl

---
 R/utils.R      |  5 +++++
 R/yaml_write.R | 33 +++++++++++++++++++++------------
 2 files changed, 26 insertions(+), 12 deletions(-)

diff --git a/R/utils.R b/R/utils.R
index e47881f74..047f61e0c 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -1732,3 +1732,8 @@ deparse_expr <- function(expr, collapse = " ", ...) {
     paste("<expr>", deparsed)
   }
 }
+
+string_is_valid_symbol <- function(x) {
+  rlang::is_scalar_character(x) &&
+    identical(make.names(x), x)
+}
diff --git a/R/yaml_write.R b/R/yaml_write.R
index ac62e42af..3a95adfc8 100644
--- a/R/yaml_write.R
+++ b/R/yaml_write.R
@@ -966,12 +966,7 @@ prune_lst_step <- function(lst_step) {
 
 as_agent_yaml_list <- function(agent, expanded) {
 
-  if (is.null(agent$read_fn)) {
-    stop(
-      "The agent must have a `tbl` value that can be put into YAML.",
-       call. = FALSE
-    )
-  }
+  check_lazy_tbl(agent, "agent")
 
   action_levels_default <- as_action_levels(agent$actions)
   end_fns <- agent$end_fns %>% unlist()
@@ -1574,12 +1569,7 @@ get_column_text <- function(step_list, expanded) {
 
 as_informant_yaml_list <- function(informant) {
 
-  if (is.null(informant$read_fn)) {
-    stop(
-      "The informant must have a `tbl` value that can be put into YAML.",
-      call. = FALSE
-    )
-  }
+  check_lazy_tbl(informant, "informant")
 
   lst_tbl_name <- to_list_tbl_name(informant$tbl_name)
   lst_read_fn <- to_list_read_fn(informant$read_fn)
@@ -1664,3 +1654,22 @@ as_tbl_store_yaml_list <- function(tbl_store) {
     lst_init                      # initialization statement
   )
 }
+
+check_lazy_tbl <- function(x, type = c("agent", "informant")) {
+  type <- match.arg(type)
+  tbl_name <- x$tbl_name
+  if (is.null(x$read_fn)) {
+    cli::cli_abort(c(
+      "x" = "The {type} must have a `tbl` value that can be put into YAML.",
+      "i" = if (string_is_valid_symbol(tbl_name)) {
+        paste(
+          "Did you mean to pass the table lazily?",
+          "{.code create_{type}(tbl = ~ {tbl_name})}"
+        )
+      } else {
+        "See {.code ?yaml_write} for details."
+      }
+    ), call = NULL)
+  }
+}
+

From b5faf30cc166cacf8a2e15bd9f50a32dc76d431f Mon Sep 17 00:00:00 2001
From: yjunechoe <jchoe001@gmail.com>
Date: Sat, 15 Feb 2025 16:21:09 -0500
Subject: [PATCH 2/4] tweak msg

---
 R/yaml_write.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/yaml_write.R b/R/yaml_write.R
index 3a95adfc8..ef7d308ba 100644
--- a/R/yaml_write.R
+++ b/R/yaml_write.R
@@ -1664,7 +1664,7 @@ check_lazy_tbl <- function(x, type = c("agent", "informant")) {
       "i" = if (string_is_valid_symbol(tbl_name)) {
         paste(
           "Did you mean to pass the table lazily?",
-          "{.code create_{type}(tbl = ~ {tbl_name})}"
+          "Ex: {.code create_{type}(tbl = ~ {tbl_name})}"
         )
       } else {
         "See {.code ?yaml_write} for details."

From d08b6e8807c6d1954cc1d8f639e756480c8bdff0 Mon Sep 17 00:00:00 2001
From: yjunechoe <jchoe001@gmail.com>
Date: Sat, 15 Feb 2025 21:26:56 -0500
Subject: [PATCH 3/4] fix lint

---
 R/yaml_write.R | 1 -
 1 file changed, 1 deletion(-)

diff --git a/R/yaml_write.R b/R/yaml_write.R
index ef7d308ba..a1167be57 100644
--- a/R/yaml_write.R
+++ b/R/yaml_write.R
@@ -1672,4 +1672,3 @@ check_lazy_tbl <- function(x, type = c("agent", "informant")) {
     ), call = NULL)
   }
 }
-

From 110bf0412956b5f6c71349425deaed487639f6c2 Mon Sep 17 00:00:00 2001
From: yjunechoe <jchoe001@gmail.com>
Date: Sat, 15 Feb 2025 21:27:48 -0500
Subject: [PATCH 4/4] add news item

---
 NEWS.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index 69d7dc6c4..1b1e69e76 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -2,6 +2,8 @@
 
 - `info_columns()` warn more informatively when no columns are selected (#589).
 
+- `write_yaml()` errors more informatively when `tbl` value is incompatible for yaml-writing (#597)
+
 - Data extracts for `rows_distinct()`/`rows_complete()` preserves all columns, not just the ones tested (#588, #591)
 
 - The `brief` argument of validation functions now also supports `{glue}` syntax (#587)