Cancel scheduled evaluation on error (#1688)

assets/js/hooks/session.js

@@ -280,6 +280,7 @@ const Session = {
   faviconForEvaluationStatus(evaluationStatus) {
     if (evaluationStatus === "evaluating") return "favicon-evaluating";
     if (evaluationStatus === "stale") return "favicon-stale";
+    if (evaluationStatus === "errored") return "favicon-errored";
     return "favicon";
   },
 

lib/livebook/live_markdown/export.ex

@@ -68,11 +68,8 @@ defmodule Livebook.LiveMarkdown.Export do
   end
 
   defp notebook_metadata(notebook) do
-    put_unless_default(
+    keys = [:persist_outputs, :autosave_interval_s]
-      %{},
+    put_unless_default(%{}, Map.take(notebook, keys), Map.take(Notebook.new(), keys))
-      Map.take(notebook, [:persist_outputs, :autosave_interval_s]),
-      Map.take(Notebook.new(), [:persist_outputs, :autosave_interval_s])
-    )
   end
 
   defp render_section(section, notebook, ctx) do
@@ -148,11 +145,8 @@ defmodule Livebook.LiveMarkdown.Export do
   end
 
   defp cell_metadata(%Cell.Code{} = cell) do
-    put_unless_default(
+    keys = [:disable_formatting, :reevaluate_automatically, :continue_on_error]
-      %{},
+    put_unless_default(%{}, Map.take(cell, keys), Map.take(Cell.Code.new(), keys))
-      Map.take(cell, [:disable_formatting, :reevaluate_automatically]),
-      Map.take(Cell.Code.new(), [:disable_formatting, :reevaluate_automatically])
-    )
   end
 
   defp cell_metadata(_cell), do: %{}

lib/livebook/live_markdown/import.ex

@@ -393,6 +393,9 @@ defmodule Livebook.LiveMarkdown.Import do
       {"reevaluate_automatically", reevaluate_automatically}, attrs ->
         Map.put(attrs, :reevaluate_automatically, reevaluate_automatically)
 
+      {"continue_on_error", continue_on_error}, attrs ->
+        Map.put(attrs, :continue_on_error, continue_on_error)
+
       _entry, attrs ->
         attrs
     end)

lib/livebook/notebook/cell/code.ex

@@ -6,7 +6,14 @@ defmodule Livebook.Notebook.Cell.Code do
   # It consists of text content that the user can edit
   # and produces some output once evaluated.
 
-  defstruct [:id, :source, :outputs, :disable_formatting, :reevaluate_automatically]
+  defstruct [
+    :id,
+    :source,
+    :outputs,
+    :disable_formatting,
+    :reevaluate_automatically,
+    :continue_on_error
+  ]
 
   alias Livebook.Utils
   alias Livebook.Notebook.Cell
@@ -16,7 +23,8 @@ defmodule Livebook.Notebook.Cell.Code do
           source: String.t() | :__pruned__,
           outputs: list(Cell.indexed_output()),
           disable_formatting: boolean(),
-          reevaluate_automatically: boolean()
+          reevaluate_automatically: boolean(),
+          continue_on_error: boolean()
         }
 
   @doc """
@@ -29,7 +37,8 @@ defmodule Livebook.Notebook.Cell.Code do
       source: "",
       outputs: [],
       disable_formatting: false,
-      reevaluate_automatically: false
+      reevaluate_automatically: false,
+      continue_on_error: false
     }
   end
 end

lib/livebook/runtime.ex

@@ -78,6 +78,7 @@ defprotocol Livebook.Runtime do
   dependencies between evaluations and avoids unnecessary reevaluations.
   """
   @type evaluation_response_metadata :: %{
+          errored: boolean(),
           evaluation_time_ms: non_neg_integer(),
           code_error: code_error(),
           memory_usage: runtime_memory(),

lib/livebook/runtime/evaluator.ex

@@ -466,6 +466,7 @@ defmodule Livebook.Runtime.Evaluator do
     output = state.formatter.format_result(result)
 
     metadata = %{
+      errored: elem(result, 0) == :error,
       evaluation_time_ms: evaluation_time_ms,
       memory_usage: memory(),
       code_error: code_error,

lib/livebook/session/data.ex

@@ -88,11 +88,13 @@ defmodule Livebook.Session.Data do
   @type cell_eval_info :: %{
           validity: cell_evaluation_validity(),
           status: cell_evaluation_status(),
+          errored: boolean(),
           snapshot: snapshot(),
           evaluation_digest: String.t() | nil,
           evaluation_snapshot: snapshot() | nil,
           evaluation_time_ms: integer() | nil,
           evaluation_start: DateTime.t() | nil,
+          evaluation_end: DateTime.t() | nil,
           evaluation_number: non_neg_integer(),
           outputs_batch_number: non_neg_integer(),
           bound_to_input_ids: MapSet.t(input_id()),
@@ -1051,19 +1053,29 @@ defmodule Livebook.Session.Data do
   end
 
   defp finish_cell_evaluation(data_actions, cell, section, metadata) do
-    data_actions
+    data_actions =
-    |> update_cell_eval_info!(cell.id, fn eval_info ->
+      data_actions
-      %{
+      |> update_cell_eval_info!(cell.id, fn eval_info ->
-        eval_info
+        %{
-        | status: :ready,
+          eval_info
-          evaluation_time_ms: metadata.evaluation_time_ms,
+          | status: :ready,
-          identifiers_used: metadata.identifiers_used,
+            errored: metadata.errored,
-          identifiers_defined: metadata.identifiers_defined,
+            evaluation_time_ms: metadata.evaluation_time_ms,
-          bound_to_input_ids: eval_info.new_bound_to_input_ids
+            identifiers_used: metadata.identifiers_used,
-      }
+            identifiers_defined: metadata.identifiers_defined,
-    end)
+            bound_to_input_ids: eval_info.new_bound_to_input_ids,
-    |> update_cell_evaluation_snapshot(cell, section)
+            evaluation_end: DateTime.utc_now()
-    |> set_section_info!(section.id, evaluating_cell_id: nil)
+        }
+      end)
+      |> update_cell_evaluation_snapshot(cell, section)
+      |> set_section_info!(section.id, evaluating_cell_id: nil)
+
+    if metadata.errored and not Map.get(cell, :continue_on_error, false) do
+      data_actions
+      |> unqueue_child_cells_evaluation(cell)
+    else
+      data_actions
+    end
   end
 
   defp update_cell_evaluation_snapshot({data, _} = data_actions, cell, section) do
@@ -1241,7 +1253,8 @@ defmodule Livebook.Session.Data do
             data: data,
             # This is a rough estimate, the exact time is measured in the
             # evaluator itself
-            evaluation_start: DateTime.utc_now()
+            evaluation_start: DateTime.utc_now(),
+            evaluation_end: nil
         }
       end)
       |> set_section_info!(section.id,
@@ -1786,9 +1799,11 @@ defmodule Livebook.Session.Data do
     %{
       validity: :fresh,
       status: :ready,
+      errored: false,
       evaluation_digest: nil,
       evaluation_time_ms: nil,
       evaluation_start: nil,
+      evaluation_end: nil,
       evaluation_number: 0,
       outputs_batch_number: 0,
       bound_to_input_ids: MapSet.new(),
@@ -1797,7 +1812,8 @@ defmodule Livebook.Session.Data do
       identifiers_defined: %{},
       snapshot: nil,
       evaluation_snapshot: nil,
-      data: nil
+      data: nil,
+      reevaluates_automatically: false
     }
   end
 
@@ -1923,6 +1939,7 @@ defmodule Livebook.Session.Data do
     data_actions
     |> compute_snapshots()
     |> update_validity()
+    |> update_reevaluates_automatically()
     # After updating validity there may be new stale cells, so we check
     # if any of them is configured for automatic reevaluation
     |> maybe_queue_reevaluating_cells()
@@ -2066,15 +2083,45 @@ defmodule Livebook.Session.Data do
     end)
   end
 
+  defp update_reevaluates_automatically({data, _} = data_actions) do
+    eval_parents = cell_evaluation_parents(data)
+
+    cells_with_section = Notebook.evaluable_cells_with_section(data.notebook)
+    cell_lookup = for {cell, _section} <- cells_with_section, into: %{}, do: {cell.id, cell}
+
+    reduce(data_actions, cells_with_section, fn data_actions, {cell, _section} ->
+      info = data.cell_infos[cell.id]
+
+      # Note that we disable automatic reevaluation if any evaluation
+      # parent errored (unless continue-on-error is enabled)
+      reevaluates_automatically =
+        Map.get(cell, :reevaluate_automatically, false) and
+          info.eval.validity in [:evaluated, :stale] and
+          not Enum.any?(eval_parents[cell.id], fn parent_id ->
+            errored? = data.cell_infos[parent_id].eval.errored
+            continue_on_error? = Map.get(cell_lookup[parent_id], :continue_on_error, false)
+            errored? and not continue_on_error?
+          end)
+
+      if reevaluates_automatically == info.eval.reevaluates_automatically do
+        data_actions
+      else
+        update_cell_eval_info!(
+          data_actions,
+          cell.id,
+          &%{&1 | reevaluates_automatically: reevaluates_automatically}
+        )
+      end
+    end)
+  end
+
   defp maybe_queue_reevaluating_cells({data, _} = data_actions) do
     cells_to_reevaluate =
       data.notebook
       |> Notebook.evaluable_cells_with_section()
       |> Enum.filter(fn {cell, _section} ->
         info = data.cell_infos[cell.id]
-
+        match?(%{status: :ready, validity: :stale, reevaluates_automatically: true}, info.eval)
-        info.eval.status == :ready and info.eval.validity == :stale and
-          Map.get(cell, :reevaluate_automatically, false)
       end)
 
     data_actions

lib/livebook_web/live/session_live.ex

@@ -2031,15 +2031,29 @@ defmodule LivebookWeb.SessionLive do
   end
 
   defp cells_status(cells, data) do
+    eval_infos =
+      for cell <- cells,
+          Cell.evaluable?(cell),
+          info = data.cell_infos[cell.id].eval,
+          do: Map.put(info, :id, cell.id)
+
+    most_recent =
+      eval_infos
+      |> Enum.filter(& &1.evaluation_end)
+      |> Enum.max_by(& &1.evaluation_end, DateTime, fn -> nil end)
+
     cond do
-      evaluating = Enum.find(cells, &evaluating?(&1, data)) ->
+      evaluating = Enum.find(eval_infos, &(&1.status == :evaluating)) ->
         {:evaluating, evaluating.id}
 
-      stale = Enum.find(cells, &stale?(&1, data)) ->
+      most_recent != nil and most_recent.errored ->
+        {:errored, most_recent.id}
+
+      stale = Enum.find(eval_infos, &(&1.validity == :stale)) ->
         {:stale, stale.id}
 
-      evaluated = Enum.find(Enum.reverse(cells), &evaluated?(&1, data)) ->
+      most_recent != nil ->
-        {:evaluated, evaluated.id}
+        {:evaluated, most_recent.id}
 
       true ->
         {:fresh, nil}
@@ -2055,18 +2069,6 @@ defmodule LivebookWeb.SessionLive do
     cells_status(cells, data)
   end
 
-  defp evaluating?(cell, data) do
-    get_in(data.cell_infos, [cell.id, :eval, :status]) == :evaluating
-  end
-
-  defp stale?(cell, data) do
-    get_in(data.cell_infos, [cell.id, :eval, :validity]) == :stale
-  end
-
-  defp evaluated?(cell, data) do
-    get_in(data.cell_infos, [cell.id, :eval, :validity]) == :evaluated
-  end
-
   defp section_views(sections, data) do
     sections
     |> Enum.map(& &1.name)
@@ -2142,6 +2144,8 @@ defmodule LivebookWeb.SessionLive do
       outputs: cell.outputs,
       validity: eval_info.validity,
       status: eval_info.status,
+      errored: eval_info.errored,
+      reevaluates_automatically: eval_info.reevaluates_automatically,
       evaluation_time_ms: eval_info.evaluation_time_ms,
       evaluation_start: eval_info.evaluation_start,
       evaluation_digest: encode_digest(eval_info.evaluation_digest),

lib/livebook_web/live/session_live/cell_component.ex

@@ -68,6 +68,7 @@ defmodule LivebookWeb.SessionLive.CellComponent do
           validity={@cell_view.eval.validity}
           status={@cell_view.eval.status}
           reevaluate_automatically={@cell_view.reevaluate_automatically}
+          reevaluates_automatically={@cell_view.eval.reevaluates_automatically}
         />
       </:primary>
       <:secondary>
@@ -167,6 +168,7 @@ defmodule LivebookWeb.SessionLive.CellComponent do
           validity={@cell_view.eval.validity}
           status={@cell_view.eval.status}
           reevaluate_automatically={false}
+          reevaluates_automatically={@cell_view.eval.reevaluates_automatically}
         />
       </:primary>
       <:secondary>
@@ -307,7 +309,7 @@ defmodule LivebookWeb.SessionLive.CellComponent do
         data-cell-id={@cell_id}
       >
         <%= cond do %>
-          <% @reevaluate_automatically and @validity in [:evaluated, :stale] -> %>
+          <% @reevaluates_automatically -> %>
             <.remix_icon icon="check-line" class="text-xl" />
             <span class="text-sm font-medium">Reevaluates automatically</span>
           <% @validity == :evaluated -> %>
@@ -653,7 +655,7 @@ defmodule LivebookWeb.SessionLive.CellComponent do
   defp cell_status(%{cell_view: %{eval: %{validity: :evaluated}}} = assigns) do
     ~H"""
     <.status_indicator
-      circle_class="bg-green-bright-400"
+      circle_class={if(@cell_view.eval.errored, do: "bg-red-400", else: "bg-green-bright-400")}
       change_indicator={true}
       tooltip={evaluated_label(@cell_view.eval.evaluation_time_ms)}
     >

lib/livebook_web/live/session_live/code_cell_settings_component.ex

@@ -12,6 +12,7 @@ defmodule LivebookWeb.SessionLive.CodeCellSettingsComponent do
       |> assign(assigns)
       |> assign_new(:disable_formatting, fn -> cell.disable_formatting end)
       |> assign_new(:reevaluate_automatically, fn -> cell.reevaluate_automatically end)
+      |> assign_new(:continue_on_error, fn -> cell.continue_on_error end)
 
     {:ok, socket}
   end
@@ -38,6 +39,13 @@ defmodule LivebookWeb.SessionLive.CodeCellSettingsComponent do
             checked={@reevaluate_automatically}
           />
         </div>
+        <div class="w-full flex-col space-y-6 mt-4">
+          <.switch_checkbox
+            name="continue_on_error"
+            label="Continue on error"
+            checked={@continue_on_error}
+          />
+        </div>
         <div class="mt-8 flex justify-begin space-x-2">
           <button class="button-base button-blue" type="submit">
             Save
@@ -54,16 +62,19 @@ defmodule LivebookWeb.SessionLive.CodeCellSettingsComponent do
         "save",
         %{
           "enable_formatting" => enable_formatting,
-          "reevaluate_automatically" => reevaluate_automatically
+          "reevaluate_automatically" => reevaluate_automatically,
+          "continue_on_error" => continue_on_error
         },
         socket
       ) do
     disable_formatting = enable_formatting == "false"
     reevaluate_automatically = reevaluate_automatically == "true"
+    continue_on_error = continue_on_error == "true"
 
     Session.set_cell_attributes(socket.assigns.session.pid, socket.assigns.cell.id, %{
       disable_formatting: disable_formatting,
-      reevaluate_automatically: reevaluate_automatically
+      reevaluate_automatically: reevaluate_automatically,
+      continue_on_error: continue_on_error
     })
 
     {:noreply, push_patch(socket, to: socket.assigns.return_to)}

lib/livebook_web/live/session_live/indicators_component.ex

@@ -190,6 +190,21 @@ defmodule LivebookWeb.SessionLive.IndicatorsComponent do
     """
   end
 
+  defp global_status(%{status: :errored} = assigns) do
+    ~H"""
+    <span class="tooltip left" data-tooltip="Go to last evaluated cell">
+      <button
+        class="border-red-300 icon-button icon-outlined-button hover:bg-red-50 focus:bg-red-50"
+        aria-label="go to last evaluated cell"
+        data-el-focus-cell-button
+        data-target={@cell_id}
+      >
+        <.remix_icon icon="loader-3-line" class="text-xl text-red-400" />
+      </button>
+    </span>
+    """
+  end
+
   defp global_status(%{status: :stale} = assigns) do
     ~H"""
     <span class="tooltip left" data-tooltip="Go to first stale cell">

static/favicon-errored.svg

@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg version="1.1" id="svg2" xml:space="preserve" width="823.87854" height="901.65137" viewBox="0 0 823.87854 901.65133" sodipodi:docname="favicon-errored.svg" inkscape:version="1.2.2 (b0a84865, 2022-12-01)" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2000/svg" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
+  <metadata id="metadata8">
+    <rdf:RDF>
+      <cc:Work rdf:about="">
+        <dc:format>
+          image/svg+xml
+        </dc:format>
+        <dc:type rdf:resource="http://purl.org/dc/dcmitype/StillImage"/>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <defs id="defs6">
+    <clipPath clipPathUnits="userSpaceOnUse" id="clipPath20">
+      <path d="M 0,805.333 H 3800 V 0 H 0 Z" id="path18"/>
+    </clipPath>
+    <clipPath clipPathUnits="userSpaceOnUse" id="clipPath148">
+      <path d="M 353.619,544.464 H 573.136 V 440.053 H 353.619 Z" id="path146"/>
+    </clipPath>
+    <clipPath clipPathUnits="userSpaceOnUse" id="clipPath172">
+      <path d="m 351.9,352.883 h 95.147 V 122.614 H 351.9 Z" id="path170"/>
+    </clipPath>
+    <clipPath clipPathUnits="userSpaceOnUse" id="clipPath1292">
+      <path id="path1294" style="fill:#000000;fill-opacity:1;stroke-width:7.50045;stroke-linecap:round;stroke-linejoin:round" d="m 202.05067,751.83844 c -9.972,0 -18,-8.028 -18,-18 V -10.124963 c 0,-9.971978 8.028,-17.999978 18,-17.999978 h 710.98537 c 9.972,0 18,8.028 18,17.999978 V 733.83844 c 0,9.972 -8.028,18 -18,18 z M 696.25088,372.24907 a 187.35425,187.35425 0 0 0 0.2417,0 A 187.35425,187.35425 0 0 0 883.84609,184.89408 187.35425,187.35425 0 0 0 696.49258,-2.4594376 187.35425,187.35425 0 0 0 509.1376,184.89408 187.35425,187.35425 0 0 0 696.25088,372.24907 Z"/>
+    </clipPath>
+  </defs>
+  <sodipodi:namedview pagecolor="#ffffff" bordercolor="#666666" borderopacity="1" objecttolerance="10" gridtolerance="10" guidetolerance="10" inkscape:pageopacity="0" inkscape:pageshadow="2" inkscape:window-width="1920" inkscape:window-height="1027" id="namedview4" showgrid="false" inkscape:zoom="0.48408519" inkscape:cx="480.28736" inkscape:cy="837.66248" inkscape:window-x="584" inkscape:window-y="25" inkscape:window-maximized="0" inkscape:current-layer="g10" inkscape:document-rotation="0" inkscape:showpageshadow="2" inkscape:pagecheckerboard="0" inkscape:deskcolor="#d1d1d1"/>
+  <g id="g10" inkscape:groupmode="layer" inkscape:label="editable_Livebook_Logo" transform="matrix(1.3333333,0,0,-1.3333333,-271.62159,986.33208)">
+    <g id="g14" clip-path="url(#clipPath1292)">
+      <g id="g16" clip-path="url(#clipPath20)">
+        <g id="g118" transform="translate(425.3255,680.1453)">
+          <path d="M 0,0 C 27.577,33.093 44.051,35.111 44.303,34.988 53.563,33.872 54.75,25.563 54.75,25.563 L 48.815,7.759 36.397,-25.372 c -12.991,2.166 -50.193,4.688 -52.949,3.31 z" style="fill:#825161;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path120"/>
+        </g>
+        <g id="g122" transform="translate(465.032,662.4954)">
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+        </g>
+        <g id="g126" transform="translate(416.4956,669.1141)">
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+        </g>
+        <g id="g138" transform="translate(354.1892,303.2845)">
+          <path d="m 0,0 c -0.044,-10.08 2.465,-20.009 7.354,-28.825 9.226,-16.633 29.838,-42.629 75.711,-72.288 52.438,-33.904 146.912,-63.851 146.912,-63.851 l 13.238,291.422 c 0,0 -243.836,115.46 -243.836,197.646 C -0.621,326.15 0.245,55.466 0,0" style="fill:#dbd8d5;fill-opacity:1;fill-rule:evenodd;stroke:none" id="path140"/>
+        </g>
+        <g id="g142">
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+            <g clip-path="url(#clipPath148)" opacity="0.25" id="g154">
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+              </g>
+            </g>
+          </g>
+        </g>
+        <g id="g158" transform="translate(293.3445,165.7054)">
+          <path d="m 0,0 c -3.146,1.255 -5.206,4.305 -5.196,7.692 l 0.424,376.462 c -0.11,2.985 0.066,7.804 5.48,5.636 L 262.142,286.099 c 0,-3.309 0.015,-2.127 0,-5.516 l -0.648,-371.921 c -0.021,-4.584 0.648,-7.544 0.648,-10.854 C 262.142,-102.82 0,0 0,0" style="fill:#c24063;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path160"/>
+        </g>
+        <g id="g162" transform="translate(555.4861,63.5135)">
+          <path d="m 0,0 260.943,102.192 c 3.146,1.255 5.206,4.305 5.196,7.692 l -0.424,376.462 c 0.061,1.642 -0.271,3.506 -1.483,4.489 -0.99,0.804 -2.569,1.019 -5.004,0.043 L 0,388.291 c 0,-4.413 -0.015,-2.127 0,-5.516 L -0.551,10.854 C -0.525,5.032 0,3.31 0,0" style="fill:#ff87a7;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path164"/>
+        </g>
+        <g id="g166">
+          <g id="g168"/>
+          <g id="g180">
+            <g clip-path="url(#clipPath172)" opacity="0.25" id="g178">
+              <g transform="translate(396.6399,125.2874)" id="g176">
+                <path d="m 0,0 c 0,0 25.629,-13.707 41.918,20.958 16.816,35.79 11.031,138.991 -39.073,206.638 0,0 33.557,-168.029 -47.585,-209.748 z" style="fill:#36272b;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path174"/>
+              </g>
+            </g>
+          </g>
+        </g>
+        <g id="g182" transform="translate(235.1873,329.8465)">
+          <path d="m 0,0 -6.929,-91.382 c -1.889,-24.9 6.023,-49.032 22.274,-67.955 16.147,-18.923 39.281,-30.415 63.952,-32.286 5.208,-0.395 10.484,-0.359 15.781,0.124 44.579,4.068 80.894,42.703 84.471,89.866 l 3.337,44.017 C 187.631,4.953 156.231,63.07 102.889,90.441 59.026,112.964 14.225,107.04 -30.368,72.879 -9.406,54.897 2.1,27.688 0,0" style="fill:#1f2728;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path184"/>
+        </g>
+        <g id="g186" transform="translate(311.2022,170.5091)">
+          <path d="m 0,0 c -16.25,18.924 -24.162,43.056 -22.274,67.956 l 6.93,91.381 c 2.099,27.689 -9.406,54.898 -30.368,72.879 16.567,12.692 33.162,21.478 49.728,26.364 -36.867,10.985 -74.257,2.169 -111.502,-26.364 20.962,-17.981 32.468,-45.19 30.368,-72.879 l -6.929,-91.381 c -1.889,-24.9 6.023,-49.032 22.274,-67.956 16.147,-18.922 39.281,-30.415 63.952,-32.286 5.208,-0.395 10.484,-0.359 15.781,0.125 7.571,0.691 14.895,2.4 21.87,4.958 C 24.539,-21.832 10.724,-12.567 0,0" style="fill:#2f393d;fill-opacity:1;fill-rule:nonzero;stroke:none" id="path188"/>
+        </g>
+      </g>
+    </g>
+    <circle style="fill:#e97579;fill-opacity:1;stroke-width:10.4152;stroke-linecap:round;stroke-linejoin:round" id="path1157" cx="698.31262" cy="-185.48764" transform="scale(1,-1)" r="114.5602"/>
+    <path fill="none" d="m -530.12015,778.48595 h 18 v -18 h -18 z" id="path2" style="stroke-width:0.75"/>
+    <path d="m -522.62015,767.10695 6.894,6.89475 1.06125,-1.0605 -7.95525,-7.95525 -4.773,4.773 1.0605,1.0605 z" id="path4" style="stroke-width:0.75"/>
+  </g>
+</svg>

test/livebook/live_markdown/export_test.exs

@@ -29,6 +29,7 @@ defmodule Livebook.LiveMarkdown.ExportTest do
                   Notebook.Cell.new(:code)
                   | disable_formatting: true,
                     reevaluate_automatically: true,
+                    continue_on_error: true,
                     source: """
                     Enum.to_list(1..10)\
                     """
@@ -101,7 +102,7 @@ defmodule Livebook.LiveMarkdown.ExportTest do
 
     $x_{i} + y_{i}$
 
-    <!-- livebook:{"disable_formatting":true,"reevaluate_automatically":true} -->
+    <!-- livebook:{"continue_on_error":true,"disable_formatting":true,"reevaluate_automatically":true} -->
 
     ```elixir
     Enum.to_list(1..10)

test/livebook/live_markdown/import_test.exs

@@ -19,7 +19,7 @@ defmodule Livebook.LiveMarkdown.ImportTest do
 
     $x_{i} + y_{i}$
 
-    <!-- livebook:{"disable_formatting":true,"reevaluate_automatically":true} -->
+    <!-- livebook:{"continue_on_error":true,"disable_formatting":true,"reevaluate_automatically":true} -->
 
     ```elixir
     Enum.to_list(1..10)
@@ -80,6 +80,7 @@ defmodule Livebook.LiveMarkdown.ImportTest do
                    %Cell.Code{
                      disable_formatting: true,
                      reevaluate_automatically: true,
+                     continue_on_error: true,
                      source: """
                      Enum.to_list(1..10)\
                      """

test/livebook/session/data_test.exs

@@ -15,7 +15,14 @@ defmodule Livebook.Session.DataTest do
   defp eval_meta(opts \\ []) do
     uses = opts[:uses] || []
     defines = opts[:defines] || %{}
-    %{evaluation_time_ms: 10, identifiers_used: uses, identifiers_defined: defines}
+    errored = Keyword.get(opts, :errored, false)
+
+    %{
+      errored: errored,
+      evaluation_time_ms: 10,
+      identifiers_used: uses,
+      identifiers_defined: defines
+    }
   end
 
   describe "new/1" do
@@ -2038,8 +2045,7 @@ defmodule Livebook.Session.DataTest do
         ])
 
       operation =
-        {:add_cell_evaluation_response, @cid, "c1", @eval_resp,
+        {:add_cell_evaluation_response, @cid, "c1", @eval_resp, eval_meta(defines: %{"c1" => 1})}
-         eval_meta(%{defines: %{"c1" => 1}})}
 
       assert {:ok,
               %{
@@ -2173,6 +2179,98 @@ defmodule Livebook.Session.DataTest do
               }, _actions} = Data.apply_operation(data, operation)
     end
 
+    test "unqueues child cells if the evaluation errored" do
+      data =
+        data_after_operations!([
+          {:insert_section, @cid, 0, "s1"},
+          {:insert_cell, @cid, "s1", 0, :code, "c1", %{}},
+          {:insert_cell, @cid, "s1", 1, :code, "c2", %{}},
+          {:insert_section, @cid, 1, "s2"},
+          {:insert_cell, @cid, "s2", 0, :code, "c3", %{}},
+          {:insert_cell, @cid, "s2", 1, :code, "c4", %{}},
+          {:set_runtime, @cid, connected_noop_runtime()},
+          evaluate_cells_operations(["setup"]),
+          {:queue_cells_evaluation, @cid, ["c1", "c2", "c3", "c4"]}
+        ])
+
+      operation =
+        {:add_cell_evaluation_response, @cid, "c1", @eval_resp, eval_meta(errored: true)}
+
+      assert {:ok,
+              %{
+                cell_infos: %{
+                  "c2" => %{eval: %{status: :ready, validity: :fresh}},
+                  "c3" => %{eval: %{status: :ready, validity: :fresh}},
+                  "c4" => %{eval: %{status: :ready, validity: :fresh}}
+                },
+                section_infos: %{
+                  "s1" => %{evaluating_cell_id: nil},
+                  "s2" => %{evaluating_cell_id: nil}
+                }
+              }, []} = Data.apply_operation(data, operation)
+    end
+
+    test "disables child cells automatic reevaluation if the evaluation errored" do
+      data =
+        data_after_operations!([
+          {:insert_section, @cid, 0, "s1"},
+          {:insert_cell, @cid, "s1", 0, :code, "c1", %{}},
+          {:insert_cell, @cid, "s1", 1, :code, "c2", %{}},
+          {:insert_cell, @cid, "s1", 2, :code, "c3", %{}},
+          {:set_cell_attributes, @cid, "c3", %{reevaluate_automatically: true}},
+          {:set_runtime, @cid, connected_noop_runtime()},
+          evaluate_cells_operations(["setup", "c1", "c2", "c3"],
+            uses: %{"c2" => ["c1"], "c3" => ["c2"]}
+          ),
+          {:queue_cells_evaluation, @cid, ["c1"]}
+        ])
+
+      operation =
+        {:add_cell_evaluation_response, @cid, "c1", @eval_resp, eval_meta(errored: true)}
+
+      assert {:ok,
+              %{
+                cell_infos: %{
+                  "c2" => %{eval: %{status: :ready}},
+                  "c3" => %{eval: %{status: :ready, reevaluates_automatically: false}}
+                },
+                section_infos: %{
+                  "s1" => %{evaluating_cell_id: nil}
+                }
+              }, []} = Data.apply_operation(data, operation)
+    end
+
+    test "re-enables child cells automatic reevaluation if errored evaluation is fixed" do
+      data =
+        data_after_operations!([
+          {:insert_section, @cid, 0, "s1"},
+          {:insert_cell, @cid, "s1", 0, :code, "c1", %{}},
+          {:insert_cell, @cid, "s1", 1, :code, "c2", %{}},
+          {:insert_cell, @cid, "s1", 2, :code, "c3", %{}},
+          {:set_cell_attributes, @cid, "c3", %{reevaluate_automatically: true}},
+          {:set_runtime, @cid, connected_noop_runtime()},
+          evaluate_cells_operations(["setup", "c1", "c2", "c3"],
+            uses: %{"c2" => ["c1"], "c3" => ["c2"]}
+          ),
+          {:queue_cells_evaluation, @cid, ["c1"]},
+          {:add_cell_evaluation_response, @cid, "c1", @eval_resp, eval_meta(errored: true)},
+          {:queue_cells_evaluation, @cid, ["c1"]}
+        ])
+
+      operation = {:add_cell_evaluation_response, @cid, "c1", @eval_resp, eval_meta()}
+
+      assert {:ok,
+              %{
+                cell_infos: %{
+                  "c2" => %{eval: %{status: :evaluating}},
+                  "c3" => %{eval: %{status: :queued, reevaluates_automatically: true}}
+                },
+                section_infos: %{
+                  "s1" => %{evaluating_cell_id: "c2"}
+                }
+              }, _actions} = Data.apply_operation(data, operation)
+    end
+
     test "if bound input value changes during cell evaluation, the cell is marked as stale afterwards" do
       input = %{id: "i1", type: :text, label: "Text", default: "hey"}
 

test/livebook/session_test.exs

@@ -7,7 +7,12 @@ defmodule Livebook.SessionTest do
   alias Livebook.Notebook.{Section, Cell}
   alias Livebook.Session.Data
 
-  @eval_meta %{evaluation_time_ms: 10, identifiers_used: [], identifiers_defined: %{}}
+  @eval_meta %{
+    errored: false,
+    evaluation_time_ms: 10,
+    identifiers_used: [],
+    identifiers_defined: %{}
+  }
 
   setup do
     session = start_session()