1 files changed, 361 insertions, 0 deletions
diff --git a/devtools/client/debugger/src/reducers/sources.js b/devtools/client/debugger/src/reducers/sources.js
new file mode 100644
index 0000000000..0d1c55be13
--- /dev/null
+++ b/devtools/client/debugger/src/reducers/sources.js
@@ -0,0 +1,361 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
+
+/**
+ * Sources reducer
+ * @module reducers/sources
+ */
+
+import { originalToGeneratedId } from "devtools/client/shared/source-map-loader/index";
+import { prefs } from "../utils/prefs";
+import { createPendingSelectedLocation } from "../utils/location";
+
+export function initialSourcesState(state) {
+  /* eslint sort-keys: "error" */
+  return {
+    /**
+     * List of all breakpoint positions for all sources (generated and original).
+     * Map of source id (string) to dictionary object whose keys are line numbers
+     * and values of array of positions.
+     * A position is an object made with two attributes:
+     * location and generatedLocation. Both refering to breakpoint positions
+     * in original and generated sources.
+     * In case of generated source, the two location will be the same.
+     *
+     * Map(source id => Dictionary(int => array<Position>))
+     */
+    mutableBreakpointPositions: new Map(),
+
+    /**
+     * List of all breakable lines for original sources only.
+     *
+     * Map(source id => array<int : breakable line numbers>)
+     */
+    mutableOriginalBreakableLines: new Map(),
+
+    /**
+     * Map of the source id's to one or more related original source id's
+     * Only generated sources which have related original sources will be maintained here.
+     *
+     * Map(source id => array<Original Source ID>)
+     */
+    mutableOriginalSources: new Map(),
+
+    /**
+     * List of override objects whose sources texts have been locally overridden.
+     *
+     * Object { sourceUrl, path }
+     */
+    mutableOverrideSources: state?.mutableOverrideSources || new Map(),
+
+    /**
+     * Mapping of source id's to one or more source-actor's.
+     * Dictionary whose keys are source id's and values are arrays
+     * made of all the related source-actor's.
+     * Note: The source mapped here are only generated sources.
+     *
+     * "source" are the objects stored in this reducer, in the `sources` attribute.
+     * "source-actor" are the objects stored in the "source-actors.js" reducer, in its `sourceActors` attribute.
+     *
+     * Map(source id => array<Source Actor object>)
+     */
+    mutableSourceActors: new Map(),
+
+    /**
+     * All currently available sources.
+     *
+     * See create.js: `createSourceObject` method for the description of stored objects.
+     */
+    mutableSources: new Map(),
+
+    /**
+     * All sources associated with a given URL. When using source maps, multiple
+     * sources can have the same URL.
+     *
+     * Map(url => array<source>)
+     */
+    mutableSourcesPerUrl: new Map(),
+
+    /**
+     * When we want to select a source that isn't available yet, use this.
+     * The location object should have a url attribute instead of a sourceId.
+     *
+     * See `createPendingSelectedLocation` for the definition of this object.
+     */
+    pendingSelectedLocation: prefs.pendingSelectedLocation,
+
+    /**
+     * The actual currently selected location.
+     * Only set if the related source is already registered in the sources reducer.
+     * Otherwise, pendingSelectedLocation should be used. Typically for sources
+     * which are about to be created.
+     *
+     * It also includes line and column information.
+     *
+     * See `createLocation` for the definition of this object.
+     */
+    selectedLocation: undefined,
+
+    /**
+     * By default, if we have a source-mapped source, we would automatically try
+     * to select and show the content of the original source. But, if we explicitly
+     * select a generated source, we remember this choice. That, until we explicitly
+     * select an original source.
+     * Note that selections related to non-source-mapped sources should never
+     * change this setting.
+     */
+    shouldSelectOriginalLocation: true,
+  };
+  /* eslint-disable sort-keys */
+}
+
+function update(state = initialSourcesState(), action) {
+  switch (action.type) {
+    case "ADD_SOURCES":
+      return addSources(state, action.sources);
+
+    case "ADD_ORIGINAL_SOURCES":
+      return addSources(state, action.originalSources);
+
+    case "INSERT_SOURCE_ACTORS":
+      return insertSourceActors(state, action);
+
+    case "SET_SELECTED_LOCATION": {
+      let pendingSelectedLocation = null;
+
+      if (action.location.source.url) {
+        pendingSelectedLocation = createPendingSelectedLocation(
+          action.location
+        );
+        prefs.pendingSelectedLocation = pendingSelectedLocation;
+      }
+
+      return {
+        ...state,
+        selectedLocation: action.location,
+        pendingSelectedLocation,
+        shouldSelectOriginalLocation: action.shouldSelectOriginalLocation,
+      };
+    }
+
+    case "CLEAR_SELECTED_LOCATION": {
+      const pendingSelectedLocation = { url: "" };
+      prefs.pendingSelectedLocation = pendingSelectedLocation;
+
+      return {
+        ...state,
+        selectedLocation: null,
+        pendingSelectedLocation,
+      };
+    }
+
+    case "SET_PENDING_SELECTED_LOCATION": {
+      const pendingSelectedLocation = {
+        url: action.url,
+        line: action.line,
+        column: action.column,
+      };
+
+      prefs.pendingSelectedLocation = pendingSelectedLocation;
+      return { ...state, pendingSelectedLocation };
+    }
+
+    case "SET_ORIGINAL_BREAKABLE_LINES": {
+      state.mutableOriginalBreakableLines.set(
+        action.sourceId,
+        action.breakableLines
+      );
+
+      return {
+        ...state,
+      };
+    }
+
+    case "ADD_BREAKPOINT_POSITIONS": {
+      // Merge existing and new reported position if some where already stored
+      let positions = state.mutableBreakpointPositions.get(action.source.id);
+      if (positions) {
+        positions = { ...positions, ...action.positions };
+      } else {
+        positions = action.positions;
+      }
+
+      state.mutableBreakpointPositions.set(action.source.id, positions);
+
+      return {
+        ...state,
+      };
+    }
+
+    case "REMOVE_THREAD": {
+      return removeSourcesAndActors(state, action);
+    }
+
+    case "SET_OVERRIDE": {
+      state.mutableOverrideSources.set(action.url, action.path);
+      return state;
+    }
+
+    case "REMOVE_OVERRIDE": {
+      if (state.mutableOverrideSources.has(action.url)) {
+        state.mutableOverrideSources.delete(action.url);
+      }
+      return state;
+    }
+  }
+
+  return state;
+}
+
+/*
+ * Add sources to the sources store
+ * - Add the source to the sources store
+ * - Add the source URL to the source url map
+ */
+function addSources(state, sources) {
+  for (const source of sources) {
+    state.mutableSources.set(source.id, source);
+
+    // Update the source url map
+    const existing = state.mutableSourcesPerUrl.get(source.url);
+    if (existing) {
+      // We never return this array from selectors as-is,
+      // we either return the first entry or lookup for a precise entry
+      // so we can mutate it.
+      existing.push(source);
+    } else {
+      state.mutableSourcesPerUrl.set(source.url, [source]);
+    }
+
+    // In case of original source, maintain the mapping of generated source to original sources map.
+    if (source.isOriginal) {
+      const generatedSourceId = originalToGeneratedId(source.id);
+      let originalSourceIds =
+        state.mutableOriginalSources.get(generatedSourceId);
+      if (!originalSourceIds) {
+        originalSourceIds = [];
+        state.mutableOriginalSources.set(generatedSourceId, originalSourceIds);
+      }
+      // We never return this array out of selectors, so mutate the list
+      originalSourceIds.push(source.id);
+    }
+  }
+
+  return { ...state };
+}
+
+function removeSourcesAndActors(state, action) {
+  const {
+    mutableSourcesPerUrl,
+    mutableSources,
+    mutableOriginalSources,
+    mutableSourceActors,
+    mutableOriginalBreakableLines,
+    mutableBreakpointPositions,
+  } = state;
+
+  const newState = { ...state };
+
+  for (const removedSource of action.sources) {
+    const sourceId = removedSource.id;
+
+    // Clear the urls Map
+    const sourceUrl = removedSource.url;
+    if (sourceUrl) {
+      const sourcesForSameUrl = (
+        mutableSourcesPerUrl.get(sourceUrl) || []
+      ).filter(s => s != removedSource);
+      if (!sourcesForSameUrl.length) {
+        // All sources with this URL have been removed
+        mutableSourcesPerUrl.delete(sourceUrl);
+      } else {
+        // There are other sources still alive with the same URL
+        mutableSourcesPerUrl.set(sourceUrl, sourcesForSameUrl);
+      }
+    }
+
+    mutableSources.delete(sourceId);
+
+    // Note that the caller of this method queried the reducer state
+    // to aggregate the related original sources.
+    // So if we were having related original sources, they will be
+    // in `action.sources`.
+    mutableOriginalSources.delete(sourceId);
+
+    // If a source is removed, immediately remove all its related source actors.
+    // It can speed-up the following for loop cleaning actors.
+    mutableSourceActors.delete(sourceId);
+
+    if (removedSource.isOriginal) {
+      mutableOriginalBreakableLines.delete(sourceId);
+    }
+
+    mutableBreakpointPositions.delete(sourceId);
+
+    if (newState.selectedLocation?.source == removedSource) {
+      newState.selectedLocation = null;
+    }
+  }
+
+  for (const removedActor of action.actors) {
+    const sourceId = removedActor.source;
+    const actorsForSource = mutableSourceActors.get(sourceId);
+    // actors may have already been cleared by the previous for..loop
+    if (!actorsForSource) {
+      continue;
+    }
+    const idx = actorsForSource.indexOf(removedActor);
+    if (idx != -1) {
+      actorsForSource.splice(idx, 1);
+      // While the Map is mutable, we expect new array instance on each new change
+      mutableSourceActors.set(sourceId, [...actorsForSource]);
+    }
+
+    // Remove the entry in the Map if there is no more actors for that source
+    if (!actorsForSource.length) {
+      mutableSourceActors.delete(sourceId);
+    }
+
+    if (newState.selectedLocation?.sourceActor == removedActor) {
+      newState.selectedLocation = null;
+    }
+  }
+
+  return newState;
+}
+
+function insertSourceActors(state, action) {
+  const { sourceActors } = action;
+
+  const { mutableSourceActors } = state;
+  // The `sourceActor` objects are defined from `newGeneratedSources` action:
+  // https://searchfox.org/mozilla-central/rev/4646b826a25d3825cf209db890862b45fa09ffc3/devtools/client/debugger/src/actions/sources/newSources.js#300-314
+  for (const sourceActor of sourceActors) {
+    const sourceId = sourceActor.source;
+    // We always clone the array of source actors as we return it from selectors.
+    // So the map is mutable, but its values are considered immutable and will change
+    // anytime there is a new actor added per source ID.
+    const existing = mutableSourceActors.get(sourceId);
+    if (existing) {
+      mutableSourceActors.set(sourceId, [...existing, sourceActor]);
+    } else {
+      mutableSourceActors.set(sourceId, [sourceActor]);
+    }
+  }
+
+  const scriptActors = sourceActors.filter(
+    item => item.introductionType === "scriptElement"
+  );
+  if (scriptActors.length) {
+    // If new HTML sources are being added, we need to clear the breakpoint
+    // positions since the new source is a <script> with new breakpoints.
+    for (const { source } of scriptActors) {
+      state.mutableBreakpointPositions.delete(source);
+    }
+  }
+
+  return { ...state };
+}
+
+export default update;