Fix autoresearch crash on zero-result search queries

DESCRIPTION

@@ -1,8 +1,8 @@
 Package: pensar
 Type: Package
 Title: LLM Wiki Engine
-Version: 0.6.3.2
-Date: 2026-05-19
+Version: 0.6.3.3
+Date: 2026-06-03
 Authors@R: c(
     person("Troy", "Hernandez", role = c("aut", "cre"),
         email = "troy@cornball.ai",

NEWS.md

@@ -1,3 +1,14 @@
+# pensar 0.6.3.3 (dev)
+
+## Bug fixes
+
+* `autoresearch()` no longer crashes when a search query returns zero
+  results. Tagging the results with `date`, `source`, `query`, and
+  `angle` assigned a length-1 value onto a 0-row data.frame and errored
+  with "replacement has 1 row, data has 0". The validator now builds all
+  columns at full length before filtering empty URLs, keeping `date` and
+  `source` aligned when rows are dropped.
+
 # pensar 0.6.3.2 (dev)
 
 ## Changes

R/autoresearch_steps.R

@@ -27,8 +27,8 @@ autoresearch_run_searches <- function(queries, search_backend, program,
                 queries$query[[i]])
         raw <- search_backend(queries$query[[i]], program$max_sources_per_round)
         df <- .validate_autoresearch_search_results(raw)
-        df$query <- queries$query[[i]]
-        df$angle <- queries$angle[[i]]
+        df$query <- rep.int(queries$query[[i]], nrow(df))
+        df$angle <- rep.int(queries$angle[[i]], nrow(df))
         results[[i]] <- df
         .ar_msg(verbose, "  search ", i, "/", nrow(queries), ": ",
                 nrow(df), " ", if (nrow(df) == 1L) "result" else "results")
@@ -564,21 +564,16 @@ autoresearch_write_pages <- function(pages, vault, program, overwrite = TRUE,
         stop("search_backend() result missing column(s): ",
              paste(missing, collapse = ", "), call. = FALSE)
     }
-    out <- x[, required, drop = FALSE]
-    out$title <- as.character(out$title)
-    out$url <- as.character(out$url)
-    out$snippet <- as.character(out$snippet)
+    date <- if ("date" %in% names(x)) as.character(x$date) else rep("", nrow(x))
+    source <- if ("source" %in% names(x)) as.character(x$source) else rep("", nrow(x))
+    out <- data.frame(
+        title = as.character(x$title),
+        url = as.character(x$url),
+        snippet = as.character(x$snippet),
+        date = date,
+        source = source,
+        stringsAsFactors = FALSE)
     out <- out[nzchar(out$url),, drop = FALSE]
-    if ("date" %in% names(x)) {
-        out$date <- as.character(x$date)
-    } else {
-        out$date <- ""
-    }
-    if ("source" %in% names(x)) {
-        out$source <- as.character(x$source)
-    } else {
-        out$source <- ""
-    }
     rownames(out) <- NULL
     out
 }

inst/tinytest/test_autoresearch.R

@@ -1069,3 +1069,29 @@ setTimeLimit(cpu = Inf, elapsed = Inf, transient = FALSE)
 expect_true(!is.null(res_timeout))
 expect_equal(nrow(res_timeout$claims), 1L)
 unlink(v_timeout, recursive = TRUE)
+
+# A search query that returns zero results must not crash validation or the
+# search loop (regression: scalar date/source/query assignment onto a 0-row
+# data.frame errored with "replacement has 1 row, data has 0").
+empty_search <- function(query, n) {
+    data.frame(title = character(), url = character(),
+               snippet = character(), stringsAsFactors = FALSE)
+}
+val_empty <- pensar:::.validate_autoresearch_search_results(empty_search("q", 5L))
+expect_equal(nrow(val_empty), 0L)
+expect_true(all(c("title", "url", "snippet", "date", "source") %in%
+                names(val_empty)))
+
+# The url filter must keep date/source aligned when it drops rows.
+mixed <- data.frame(title = c("a", "b"), url = c("", "https://x.test"),
+                    snippet = c("s1", "s2"), stringsAsFactors = FALSE)
+val_mixed <- pensar:::.validate_autoresearch_search_results(mixed)
+expect_equal(nrow(val_mixed), 1L)
+expect_equal(val_mixed$url, "https://x.test")
+
+# The full search loop tags query/angle even when a query yields nothing.
+q <- data.frame(query = "q", angle = "a", stringsAsFactors = FALSE)
+loop_empty <- pensar:::autoresearch_run_searches(
+    q, empty_search, list(max_sources_per_round = 5L), verbose = FALSE)
+expect_equal(nrow(loop_empty), 0L)
+expect_true(all(c("query", "angle") %in% names(loop_empty)))