A quick tip and an easy hack to see the emerge resume list, which will be used by the “emerge –resume” command. There are two resume lists – resume and resume_backup in the binary file /var/cache/edb/mtimedb.
The first two commands are python 3+.
The resume and resume_backup lists

python -c 'import portage; print(portage.mtimedb.get("resume", {}).get("mergelist"))'
python -c 'import portage; print(portage.mtimedb.get("resume_backup", {}).get("mergelist"))'

If you need the command for the python 2 you should use the following:

python -c 'import portage; print portage.mtimedb.get("resume", {}).get("mergelist")'
python -c 'import portage; print portage.mtimedb.get("resume_backup", {}).get("mergelist")'

Real world example

Resume list for

desktop ~ # emerge -v --nodeps $(qlist -IC|grep dev-qt)

These are the packages that would be merged, in order:

[ebuild     U  ] dev-qt/designer-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="declarative webkit -debug -test" 8,493 KiB
[ebuild     U  ] dev-qt/linguist-tools-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="qml -debug -test" 0 KiB
[ebuild     U  ] dev-qt/qdbus-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qtbluetooth-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -qml -test" 2,727 KiB
[ebuild   R    ] dev-qt/qtchooser-66::gentoo  USE="-test" 32 KiB
[ebuild     U  ] dev-qt/qtconcurrent-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 48,549 KiB
[ebuild     U  ] dev-qt/qtcore-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="icu -debug (-systemd) -test" 0 KiB
[ebuild     U  ] dev-qt/qtdbus-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qtdeclarative-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="jit widgets -debug -gles2 -localstorage -test" 20,753 KiB
[ebuild     U  ] dev-qt/qtgraphicaleffects-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 13,713 KiB
[ebuild     U  ] dev-qt/qtgui-5.14.0-r1:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="accessibility dbus egl evdev gif ibus jpeg libinput png udev vnc wayland%* xcb -debug -eglfs -gles2 -test -tslib -tuio" 0 KiB
[ebuild     U  ] dev-qt/qthelp-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qtimageformats-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="mng -debug -test (-jpeg2k%)" 1,768 KiB
[ebuild     U  ] dev-qt/qtlocation-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 5,974 KiB
[ebuild   R    ] dev-qt/qtlockedfile-2.4.1_p20171024::gentoo  USE="-doc" 694 KiB
[ebuild     U  ] dev-qt/qtmultimedia-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="alsa gstreamer openal pulseaudio qml widgets -debug -gles2 -test" 3,671 KiB
[ebuild     U  ] dev-qt/qtnetwork-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="libproxy networkmanager ssl -bindist -connman -debug -sctp -test" 0 KiB
[ebuild     U  ] dev-qt/qtopengl-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -gles2 -test" 0 KiB
[ebuild     U  ] dev-qt/qtpaths-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qtpositioning-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="qml -debug -geoclue -test" 0 KiB
[ebuild     U  ] dev-qt/qtprintsupport-5.14.0-r1:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="cups -debug -gles2 -test" 0 KiB
[ebuild     U  ] dev-qt/qtquickcontrols2-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test -widgets" 7,947 KiB
[ebuild     U  ] dev-qt/qtquickcontrols-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="widgets -debug -test" 5,843 KiB
[ebuild     U  ] dev-qt/qtscript-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="jit scripttools -debug -test" 2,584 KiB
[ebuild     U  ] dev-qt/qtsensors-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -qml -test" 1,996 KiB
[ebuild   R    ] dev-qt/qtsingleapplication-2.6.1_p20171024::gentoo  USE="X -doc" 0 KiB
[ebuild     U  ] dev-qt/qtspeech-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 99 KiB
[ebuild     U  ] dev-qt/qtsql-5.14.0:5/5.14.0::gentoo [5.12.2:5/5.12.2::gentoo] USE="mysql sqlite -debug -freetds -oci8 -odbc -postgres -test" 0 KiB
[ebuild     U  ] dev-qt/qtsvg-5.14.0-r1:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 1,822 KiB
[ebuild     U  ] dev-qt/qttest-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qttranslations-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 1,302 KiB
[ebuild     U  ] dev-qt/qtvirtualkeyboard-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="spell xcb -debug -handwriting -test" 10,705 KiB
[ebuild     U  ] dev-qt/qtwayland-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="libinput xcomposite -debug -test" 532 KiB
[ebuild     U  ] dev-qt/qtwebchannel-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="qml -debug -test" 192 KiB
[ebuild     U  ] dev-qt/qtwebengine-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="alsa pulseaudio system-icu widgets -bindist -debug -designer -jumbo-build -pax_kernel -system-ffmpeg -test (-geolocation%*)" 235,904 KiB
[ebuild     U  ] dev-qt/qtwebkit-5.212.0_pre20190629:5/5.212::gentoo [5.212.0_pre20180120:5/5.212::gentoo] USE="X geolocation hyphen jit multimedia opengl printsupport qml -gles2 -gstreamer -nsplugin -orientation -webp" 12,166 KiB
[ebuild     U  ] dev-qt/qtwidgets-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="gtk png xcb -debug -gles2 -test" 0 KiB
[ebuild     U  ] dev-qt/qtx11extras-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 125 KiB
[ebuild     U  ] dev-qt/qtxml-5.14.0:5/5.14::gentoo [5.12.2:5/5.12::gentoo] USE="-debug -test" 0 KiB
[ebuild     U  ] dev-qt/qtxmlpatterns-5.14.0:5/5.14::gentoo [5.11.1:5/5.11::gentoo] USE="-debug -qml% -test" 1,362 KiB

Total: 40 packages (37 upgrades, 3 reinstalls), Size of downloads: 388,941 KiB


>>> Verifying ebuild manifests
>>> Running pre-merge checks for dev-qt/qtwebkit-5.212.0_pre20190629

>>> Emerging (1 of 40) dev-qt/designer-5.14.0::gentoo
 * Fetching files in the background.
 * To view fetch progress, run in another terminal:
 * tail -f /var/log/emerge-fetch.log
 * qttools-everywhere-src-5.14.0.tar.xz BLAKE2B SHA512 size ;-) ...                                                                                                  [ ok ]
!!! Failed to set new SELinux execution context. Is your current SELinux context allowed to run Portage?
>>> Unpacking source...
>>> Unpacking qttools-everywhere-src-5.14.0.tar.xz to /var/tmp/portage/dev-qt/designer-5.14.0/work
^C

Exiting on signal 2
sandbox:stop  caught signal 2 in pid 22886
sandbox:stop  Send signal 4 more times to force SIGKILL
Sandboxed process killed by signal: Interrupt
^C * The ebuild phase 'die_hooks' has been killed by signal 2.

 * Messages for package dev-qt/designer-5.14.0:

We interrupted it on purpose with Ctrl+C.

The output of the above python command:

desktop ~ # python -c 'import portage; print(portage.mtimedb.get("resume", {}).get("mergelist"))'
[['ebuild', '/', 'dev-qt/designer-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/linguist-tools-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qdbus-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtbluetooth-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtchooser-66', 'merge'], ['ebuild', '/', 'dev-qt/qtconcurrent-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtcore-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtdbus-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtdeclarative-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtgraphicaleffects-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtgui-5.14.0-r1', 'merge'], ['ebuild', '/', 'dev-qt/qthelp-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtimageformats-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtlocation-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtlockedfile-2.4.1_p20171024', 'merge'], ['ebuild', '/', 'dev-qt/qtmultimedia-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtnetwork-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtopengl-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtpaths-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtpositioning-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtprintsupport-5.14.0-r1', 'merge'], ['ebuild', '/', 'dev-qt/qtquickcontrols2-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtquickcontrols-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtscript-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtsensors-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtsingleapplication-2.6.1_p20171024', 'merge'], ['ebuild', '/', 'dev-qt/qtspeech-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtsql-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtsvg-5.14.0-r1', 'merge'], ['ebuild', '/', 'dev-qt/qttest-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qttranslations-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtvirtualkeyboard-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtwayland-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtwebchannel-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtwebengine-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtwebkit-5.212.0_pre20190629', 'merge'], ['ebuild', '/', 'dev-qt/qtwidgets-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtx11extras-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtxml-5.14.0', 'merge'], ['ebuild', '/', 'dev-qt/qtxmlpatterns-5.14.0', 'merge']]
desktop ~ # python -c 'import portage; print(portage.mtimedb.get("resume_backup", {}).get("mergelist"))'
None