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diff --git a/devtools/client/debugger/src/selectors/breakpointAtLocation.js b/devtools/client/debugger/src/selectors/breakpointAtLocation.js
new file mode 100644
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+++ b/devtools/client/debugger/src/selectors/breakpointAtLocation.js
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+/* 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/>. */
+
+// @flow
+
+import {
+  getSelectedSource,
+  getBreakpointPositionsForLine,
+} from "../reducers/sources";
+import { getBreakpointsList } from "../reducers/breakpoints";
+import { isGenerated } from "../utils/source";
+
+import type {
+  Breakpoint,
+  BreakpointPosition,
+  PartialPosition,
+  SourceLocation,
+} from "../types";
+import type { State } from "../reducers/types";
+
+function getColumn(column, selectedSource): ?number {
+  if (column) {
+    return column;
+  }
+
+  return isGenerated(selectedSource) ? undefined : 0;
+}
+
+function getLocation(bp, selectedSource): SourceLocation {
+  return isGenerated(selectedSource)
+    ? bp.generatedLocation || bp.location
+    : bp.location;
+}
+
+function getBreakpointsForSource(state: State, selectedSource): Breakpoint[] {
+  const breakpoints = getBreakpointsList(state);
+
+  return breakpoints.filter(bp => {
+    const location = getLocation(bp, selectedSource);
+    return location.sourceId === selectedSource.id;
+  });
+}
+
+type LineColumn = { line: number, column: ?number };
+
+function findBreakpointAtLocation(
+  breakpoints,
+  selectedSource,
+  { line, column }: LineColumn
+): ?Breakpoint {
+  return breakpoints.find(breakpoint => {
+    const location = getLocation(breakpoint, selectedSource);
+    const sameLine = location.line === line;
+    if (!sameLine) {
+      return false;
+    }
+
+    if (column === undefined) {
+      return true;
+    }
+
+    return location.column === getColumn(column, selectedSource);
+  });
+}
+
+// returns the closest active column breakpoint
+function findClosestBreakpoint(breakpoints, column) {
+  if (!breakpoints || breakpoints.length == 0) {
+    return null;
+  }
+
+  const firstBreakpoint = breakpoints[0];
+  return breakpoints.reduce((closestBp, currentBp) => {
+    const currentColumn = currentBp.generatedLocation.column;
+    const closestColumn = closestBp.generatedLocation.column;
+    // check that breakpoint has a column.
+    if (column && currentColumn && closestColumn) {
+      const currentDistance = Math.abs(currentColumn - column);
+      const closestDistance = Math.abs(closestColumn - column);
+
+      return currentDistance < closestDistance ? currentBp : closestBp;
+    }
+    return closestBp;
+  }, firstBreakpoint);
+}
+
+/*
+ * Finds a breakpoint at a location (line, column) of the
+ * selected source.
+ *
+ * This is useful for finding a breakpoint when the
+ * user clicks in the gutter or on a token.
+ */
+export function getBreakpointAtLocation(
+  state: State,
+  location: LineColumn
+): ?Breakpoint {
+  const selectedSource = getSelectedSource(state);
+  if (!selectedSource) {
+    throw new Error("no selectedSource");
+  }
+  const breakpoints = getBreakpointsForSource(state, selectedSource);
+
+  return findBreakpointAtLocation(breakpoints, selectedSource, location);
+}
+
+export function getBreakpointsAtLine(state: State, line: number): Breakpoint[] {
+  const selectedSource = getSelectedSource(state);
+  if (!selectedSource) {
+    throw new Error("no selectedSource");
+  }
+  const breakpoints = getBreakpointsForSource(state, selectedSource);
+
+  return breakpoints.filter(
+    breakpoint => getLocation(breakpoint, selectedSource).line === line
+  );
+}
+
+export function getClosestBreakpoint(
+  state: State,
+  position: PartialPosition
+): ?Breakpoint {
+  const columnBreakpoints = getBreakpointsAtLine(state, position.line);
+  const breakpoint = findClosestBreakpoint(columnBreakpoints, position.column);
+  return (breakpoint: any);
+}
+
+export function getClosestBreakpointPosition(
+  state: State,
+  position: PartialPosition
+): ?BreakpointPosition {
+  const selectedSource = getSelectedSource(state);
+  if (!selectedSource) {
+    throw new Error("no selectedSource");
+  }
+
+  const columnBreakpoints = getBreakpointPositionsForLine(
+    state,
+    selectedSource.id,
+    position.line
+  );
+
+  return findClosestBreakpoint(columnBreakpoints, position.column);
+}